Omega-3 fatty acids: are supplements truly necessary for optimal brain health?

Greater intake of long-chain omega-3 fatty acids (EPA and DHA) is associated with decreased risk of brain disorders (such as Alzheimer’s disease) and cardiovascular disease.1-3 DHA is a crucial factor in early brain development because it is a major constituent of cell membranes in the brain, retina, and nervous system. There is significant evidence in the fossil record that a increase in DHA availability in the diet of early humans was responsible for the expansion of the brain into the large, complex organ it has now become.4,5 DHA requirements are the greatest in the developing brain during the last trimester of pregnancy and the first two years of life. During early life, a baby’s only source of this building block of brain and eye tissue is its mother’s milk.6,7 Several studies have documented improved cognitive scores in breastfed infants compared to formula-fed infants, prompting supplementation of infant formula with DHA in the U.S.8 But what if the “normal” amount of DHA in American women’s breast milk is still not enough? What if the developing brain requires more DHA for optimal cognitive development?

A recent study compared the fatty acid content of breast milk in American women in Cincinnati to that of Tsimane women of Bolivia. Tsimane women eat a traditional diet of primarily locally grown plant foods, wild-caught animals, and freshwater fish. The results of the study showed that the DHA concentration of Tsimane mothers’ milk was 400% higher than that of Cincinnati mothers, their concentration of linoleic acid (an omega-6 fatty acid abundant in oils) was 84% lower, and their concentration of trans fat was 260% lower than in Cincinnati mothers.9,10 In a previous analysis, pooling data from 84 studies of breast milk DHA concentrations in many different countries, the U.S. concentrations fell below the worldwide average. The areas with the highest breast milk DHA concentrations were coastal or island nations, suggesting that breast milk DHA concentration is closely linked to the consumption of fish.11

Our modern eating habits have transformed the fatty acid distribution of our diet.12 One of the study’s authors, Steven Gaulin, a professor of anthropology at the University of California at Santa Barbara, noted "The American diet is eroding one of the most important benefits breast milk can provide –– fats that are critical to infant brain development. It's not surprising that, among developed nations, American children are last on international tests of math and science."9

What is the “normal” DHA of content of human breast milk – or rather, the amount that will ideally support brain development in infants? We don’t know for sure. However, these huge differences between a traditional diet and a modern diet, and the high DHA concentrations in high fish-consuming countries indicate that the DHA intake of Americans may be sub-optimal for supporting brain health. The American diet is low in DHA, and high in vegetable oils and trans fats, which limit the elongation of ALA from plant foods into DHA and EPA, and displaces omega-3 fats from cell membranes.4,13 Factory-farmed meats, oils and trans fats are not the appropriate fatty fuel to grow a baby’s brain.

Does this mean that we should eat fish? From the evidence we have now, if you eat with a modern diet (even without oils) and you don’t eat fish regularly, it is almost impossible to have adequate DHA stores, especially for pregnant and nursing women.

Avoiding oils and eating plenty of hemp, chia, flax, walnuts, and leafy greens is likely still not enough, since the conversion rate of ALA (short-chain omega-3) in these foods to DHA (long-chain omega-3) is very low. Large increases in ALA intake have been shown to produce only very slight increases in long-chain omega-3 blood levels. Plus, much of the ALA we consume is burned for energy, not converted to DHA or EPA.14,15

However, modern fish is a heavily polluted food that I do not recommend eating regularly. The DHA in fish may benefit the brain, but the fatty tissues of fish is highly contaminated with mercury, and other pollutants, which could be toxic to the brain and may also contribute to cardiovascular disease.16,17 In addition to the potential effects of mercury on human health, huge declines in wild fish populations have been reported since the 1950s, and populations continue to decline as the purported benefits of fish consumption on heart and brain health increase the demand for fish and fish oils.18 Fish is not an ideal source of DHA; fortunately DHA derived from lab-grown algae is available as a supplement.

One can't really be sure they have ideal levels of omega-3 anymore without supplements. If you eat enough fish to idealize your omega-3 ratio, you get too much mercury, dioxin, and other pollutants. I think it is sensible and conservative to err on the side of caution and eat a diet that contains ALA from flax, chia, walnuts and leafy greens, not merely because of their ALA content, but also for their anti-inflammatory and anti-cancer effects. Then adding a supplement of a clean algae-derived DHA is a wise insurance policy. Significant evidence suggests that a comparatively small amount of DHA and EPA can add health protection without the potential drawbacks of high dose fish oil capsules.19-21

 

 References:

1. Yurko-Mauro K. Cognitive and cardiovascular benefits of docosahexaenoic acid in aging and cognitive decline. Curr Alzheimer Res 2010;7:190-196.
2. Yurko-Mauro K, McCarthy D, Rom D, et al. Beneficial effects of docosahexaenoic acid on cognition in age-related cognitive decline. Alzheimers Dement 2010.
3. Kris-Etherton PM, Harris WS, Appel LJ. Fish consumption, fish oil, omega-3 fatty acids, and cardiovascular disease. Circulation 2002;106:2747-2757.
4. Crawford MA, Broadhurst CL. The role of docosahexaenoic and the marine food web as determinants of evolution and hominid brain development: the challenge for human sustainability. Nutr Health 2012;21:17-39.
5. Bradbury J. Docosahexaenoic acid (DHA): an ancient nutrient for the modern human brain. Nutrients 2011;3:529-554.
6. Ryan AS, Astwood JD, Gautier S, et al. Effects of long-chain polyunsaturated fatty acid supplementation on neurodevelopment in childhood: a review of human studies. Prostaglandins Leukot Essent Fatty Acids 2010;82:305-314.
7. Kidd PM. Omega-3 DHA and EPA for cognition, behavior, and mood: clinical findings and structural-functional synergies with cell membrane phospholipids. Altern Med Rev 2007;12:207-227.
8. Hoffman DR, Boettcher JA, Diersen-Schade DA. Toward optimizing vision and cognition in term infants by dietary docosahexaenoic and arachidonic acid supplementation: a review of randomized controlled trials. Prostaglandins Leukot Essent Fatty Acids 2009;81:151-158.
9. UCSB anthropologists finds high levels of omega-3 fatty acids in breast milk of Amerindian women. 2012. EurekAlert! http://www.eurekalert.org/pub_releases/2012-06/uoc--uaf060812.php. Accessed August 15, 2012.
10. Martin MA, Lassek WD, Gaulin SJ, et al. Fatty acid composition in the mature milk of Bolivian forager-horticulturalists: controlled comparisons with a US sample. Matern Child Nutr 2012;8:404-418.
11. Brenna JT, Varamini B, Jensen RG, et al. Docosahexaenoic and arachidonic acid concentrations in human breast milk worldwide. Am J Clin Nutr 2007;85:1457-1464.
12. Blasbalg TL, Hibbeln JR, Ramsden CE, et al. Changes in consumption of omega-3 and omega-6 fatty acids in the United States during the 20th century. Am J Clin Nutr 2011.
13. Harnack K, Andersen G, Somoza V. Quantitation of alpha-linolenic acid elongation to eicosapentaenoic and docosahexaenoic acid as affected by the ratio of n6/n3 fatty acids. Nutr Metab 2009;6:8.
14. Arterburn LM, Hall EB, Oken H. Distribution, interconversion, and dose response of n-3 fatty acids in humans. Am J Clin Nutr 2006;83:1467S-1476S.
15. Fokkema MR, Brouwer DA, Hasperhoven MB, et al. Short-term supplementation of low-dose gamma-linolenic acid (GLA), alpha-linolenic acid (ALA), or GLA plus ALA does not augment LCP omega 3 status of Dutch vegans to an appreciable extent. Prostaglandins Leukot Essent Fatty Acids 2000;63:287-292.
16. Rice GE, Hammitt JK, Evans JS. A probabilistic characterization of the health benefits of reducing methyl mercury intake in the United States. Environmental science & technology 2010;44:5216-5224.
17. Virtanen JK, Rissanen TH, Voutilainen S, et al. Mercury as a risk factor for cardiovascular diseases. The Journal of nutritional biochemistry 2007;18:75-85.
18. Myers RA, Worm B. Rapid worldwide depletion of predatory fish communities. Nature 2003;423:280-283.
19. Musa-Veloso K, Binns MA, Kocenas A, et al: Impact of low v. moderate intakes of long-chain n-3 fatty acids on risk of coronary heart disease. Br J Nutr 2011.
20. Thies F, Nebe-von-Caron G, Powell JR, et al. Dietary supplementation with eicosapentaenoic acid, but not with other long-chain n-3 or n-6 polyunsaturated fatty acids, decreases natural killer cell activity in healthy subjects aged >55 y. Am J Clin Nutr. 2001 Mar;73(3):539-48.
21. Linus Pauling Institute: Essential Fatty Acids. http://lpi.oregonstate.edu/infocenter/othernuts/omega3fa/


 

Vitamin D recommendations have been raised, but not enough

SupplementsA few weeks ago, the Institute of Medicine (IOM) surprised many of us when it announced its new dietary reference intake (DRI) for vitamin D. The consensus of the scientific community was that the previous DRI of 400 IU was insufficient, and that supplementation with at least 1000 IU would be necessary for most people to achieve vitamin D sufficiency. The IOM disagreed.

The IOM’s new recommendations:

- Recommended intake: 600 IU per day (for children and adults under age 70)

- Tolerable upper limit (amount not to be exceeded in one day): 4000 IU (raised from 2000 IU)

- Sufficient blood 25(OH)D level: 20 ng/ml

There has been a great deal of research in recent years on vitamin D’s role in a variety of human diseases. Low vitamin D status has been associated with cardiovascular disease, certain cancers, cognitive decline, depression, diabetes, pregnancy complications, autoimmune diseases, and even a 78% increase in all-cause mortality risk (<17.8 ng/ml 25(OH)D compared to >32.1 ng/ml). [1] However, because there are not yet enough randomized controlled trials to clearly and conclusively confirm the benefits of vitamin D supplementation for conditions unrelated to bone health [2], the IOM did not find the existing evidence for non-skeletal conditions sufficient enough to raise the daily recommendations any higher than 600 IU. The 600 IU figure is based solely on bone health - they did not take into account whether a greater quantity of vitamin D might be necessary to prevent non-skeletal diseases, even though there are vitamin D receptors in almost every cell of the human body.

Many experts are weighing in on – and disagreeing with – the IOM’s report, and there is general agreement among the experts on these points:

  • The increase of the tolerable upper limit to 4000 IU is a positive change.
  • The IOM’s definition of 20 ng/ml as a sufficient 25(OH)D is potentially low, and this could be dangerous for some people
  • The lack of randomized controlled trials does not mean that we should ignore the epidemiological evidence showing vitamin D’s importance for preventing non-skeletal diseases.

Compare my recommendations to those of the IOM:

Recommendations: 25(OH)D Vitamin D supplementation (adults)
Institute of Medicine >20 ng/ml 600 IU
Dr. Fuhrman 35-55 ng/ml 2000 IU*

*adjust supplementation according to 25(OH)D level

I agree that the IOM’s recommendations are inadequate. My recommendation is a safe, conservative amount of vitamin D which is supported by the literature. To learn more about why following the IOM’s guidelines may be risky, read my full commentary.

 

References:

1. Melamed, M.L., et al., 25-Hydroxyvitamin D Levels and the Risk of Mortality in the General Population. Archives of Internal Medicine, 2008. 168(15): p. 1629-1637.
2. Zhang, R. and D.P. Naughton, Vitamin D in health and disease: Current perspectives. Nutr J, 2010. 9(65).

 

Vitamin B12 may protect against Alzheimer 's disease

Vitamin B12 is required for important biological functions like red blood cell production, nervous system function, and DNA synthesis. Deficiency in B12 can cause a variety of problems including anemia, depression, confusion, fatigue, digestive issues, and nerve damage. [1]

Vitamins. Flickr: bradley jVitamin B12 is scarce in plant-based diets, and is a common deficiency, especially in the elderly. Of course, diets low in animal products and high in unrefined plant foods dramatically reduce the risk of chronic disease, but these healthful diets do require a supplemental source of vitamin B12. The rates of deficiency increase with age, and about 20% of adults over the age of 60 are either insufficient or deficient in vitamin B12.[2] Recent research has suggested that the current recommendations for B12 intake may be inadequate – not just for the elderly, but even for young people who have adequate absorption capability. Therefore supplementation with vitamin B12 is likely important for most people, and absolutely required for most vegans to achieve sufficient B12 status.[3]

When vitamin B12 takes part in DNA synthesis, it helps to convert the amino acid homocysteine to methionine, therefore lowering homocysteine levels. [1] Elevated homocysteine is a known risk factor for cardiovascular disease. Since B12 is important for nervous system function, and many cardiovascular disease risk factors are also risk factors for Alzheimer’s disease, scientists hypothesized that adequate vitamin B12 levels would be protective, and elevated homocysteine would be detrimental with respect to the development of Alzheimer’s. They investigated the relationship between homocysteine, B12, and Alzheimer’s disease diagnosis in a group of 271 healthy older persons (65-79 years of age) over the course of 7 years. Elevated homocysteine was associated with increased risk, and increased B12 with decreased risk of Alzheimer’s disease. [4]

Future studies will evaluate the effectiveness of vitamin B12 supplementation as a preventive measure against dementia, but we don’t need to wait for those results – we already know that B12 is an important supplement to take, and Alzheimer’s prevention may turn out to be an added benefit of maintaining adequate B12 levels.

A health-promoting diet is the most effective way to maintain excellent health and protect against chronic diseases, including Alzheimer’s and other forms of dementia. But in order to enjoy the strongest protection possible, it is just as important to prevent deficiencies of certain nutrients that may be sub-optimal in an overall health-promoting diet, such as vitamin B12, zinc, DHA, and vitamin D, by taking the necessary supplements.

 

References:

1. Office of Dietary Supplements, National Institutes of Health. Dietary Supplement Fact Sheet: Vitamin B12. November 18, 2010]; Available from: http://ods.od.nih.gov/factsheets/VitaminB12/.
2. Allen, L.H., How common is vitamin B-12 deficiency? Am J Clin Nutr, 2009. 89(2): p. 693S-6S.
3. Bor, M.V., et al., Daily intake of 4 to 7 microg dietary vitamin B-12 is associated with steady concentrations of vitamin B-12-related biomarkers in a healthy young population. Am J Clin Nutr, 2010. 91(3): p. 571-7.
4. Hooshmand, B., et al., Homocysteine and holotranscobalamin and the risk of Alzheimer disease: a longitudinal study. Neurology, 2010. 75(16): p. 1408-14.

 

Vitamin D may elevate mood during the winter

The days are beginning to get shorter and we’re spending more time indoors as most of the day’s sunlit hours are occurring during the work day. For our bodies, this is a significant change to adjust to, especially for those of us who live in cooler climates. It’s common to experience some decline in mood during the winter – feelings of anxiety and depression are known to be more prevalent throughout the colder months. For some individuals, these seasonal mood changes along with fatigue, irritability, and appetite changes are especially pronounced, and this is called Seasonal Affective Disorder (SAD).[1] Incidence of SAD increases with distance from the equator, and light therapy is an effective treatment for many individuals with SAD. Reduced sunlight exposure, resulting in shifts in circadian rhythms and alterations in serotonin metabolism, is thought to underlie this condition.[2]

Timing of exposure of the retina to light affects the sleep-wake cycle, and inadequate light exposure during the winter disrupts this cycle. Light therapy independent of vitamin D production (ultraviolet light is filtered out), especially in the morning hours, is known to be effective for treating SAD and major depression. SAD has been successfully treated with light therapy since the early 1980s. For depression, a meta-analysis in 2005 revealed that the effectiveness of light therapy was comparable to that reported in many trials of anti-depressant drugs.[3] Light entry into the retina inhibits production of melatonin, a hormone that promotes sleep. Light therapy helps to restore melatonin, the neurotransmitter serotonin, and other mood-regulating molecules to their normal time cycles and levels of production; consequently depressive symptoms are reduced.[4]

Reduced exposure to sunlight during the winter also means less natural vitamin D production by the skin, , and vitamin D itself may also regulate mood. There is still much unknown about how vitamin D works in the brain, but there are plenty of vitamin D receptors in the brain, and it is thought to affect daily biorhythms and production of neurotransmitters, including serotonin.[1] Also, low circulating vitamin D is associated with SAD and major depression.[5] So far, only a handful trials of vitamin D supplementation for seasonal depressive symptoms have been performed, and some of these used doses that were likely too low to have any measurable effect (400 IU; currently many experts believe that 2000 IU/day or more may be necessary for most people to maintain adequate blood 25(OH)D levels [6]). A dose of 800 IU improved mood of healthy subjects during winter in one trial [7], but had no effect in another trial.[8] A third trial used a dose of 4000 IU/day for six months starting in the summer, and then evaluated feelings of wellbeing during the December-February time period. The 4000 IU dose of vitamin D produced an average 25(OH)D level of 45 ng/ml and improved wellbeing scores compared to a 600 IU dose (average 25(OH)D level of 32 ng/ml). [9]

Current research is investigating the connection between depression and diabetes with a focus on vitamin D. Because depression is associated with insulin resistance, and vitamin D is thought to affect insulin secretion by the pancreas, ongoing studies are evaluating whether vitamin D supplementation can help to prevent diabetes. [10] In fact, healthy adults with low vitamin D levels were more likely to develop diabetes within 10 years compared those with adequate levels, according to a recent study. [11]

Vitamin D is active in essentially every cell and tissue in the human body. It is crucial (for everyone, not just sufferers of SAD ) to maintain adequate 25(OH)D levels (Dr. Fuhrman recommends 35-55 ng/ml) with supplementation. Especially if you note mood or sleep issues during the winter, be sure to accompany vitamin D supplementation with plenty of morning light.

 

References:

1. Bertone-Johnson, E.R., Vitamin D and the occurrence of depression: causal association or circumstantial evidence? Nutr Rev, 2009. 67(8): p. 481-92.
2. Lurie, S.J., et al., Seasonal affective disorder. Am Fam Physician, 2006. 74(9): p. 1521-4.
3. Golden, R.N., et al., The efficacy of light therapy in the treatment of mood disorders: a review and meta-analysis of the evidence. Am J Psychiatry, 2005. 162(4): p. 656-62.
4. Miller, A.L., Epidemiology, etiology, and natural treatment of seasonal affective disorder. Altern Med Rev, 2005. 10(1): p. 5-13.
5. Murphy, P.K. and C.L. Wagner, Vitamin D and mood disorders among women: an integrative review. J Midwifery Womens Health, 2008. 53(5): p. 440-6.
6. University of California - Riverside (2010, July 19). More than half the world's population gets insufficient vitamin D, says biochemist. ScienceDaily July 28, 2010]; Available from: http://www.sciencedaily.com/releases/2010/07/100715172042.htm.
7. Lansdowne, A.T. and S.C. Provost, Vitamin D3 enhances mood in healthy subjects during winter. Psychopharmacology (Berl), 1998. 135(4): p. 319-23.
8. Dumville, J.C., et al., Can vitamin D supplementation prevent winter-time blues? A randomised trial among older women. J Nutr Health Aging, 2006. 10(2): p. 151-3.
9. Vieth, R., et al., Randomized comparison of the effects of the vitamin D3 adequate intake versus 100 mcg (4000 IU) per day on biochemical responses and the wellbeing of patients. Nutr J, 2004. 3: p. 8.
10. Loyola University Health System (2010, March 8). Vitamin D lifts mood during cold weather months, researchers say. ScienceDaily. . November 9, 2010]; Available from: http://www.sciencedaily.com/releases/2010/03/100303162854.htm.
11. Valencia, W., Abstract 125: Prospective risk of hyperglycemia in a South Florida population with low levels of vitamin D, in World Congress on Insulin Resistance, Diabetes and Cardiovascular Disease 2010.

 

Does omega-3 supplementation during pregnancy prevent postpartum depression? Improve baby's brain development?

Omega-3 fats are essential – we must take them in from our diets because our body cannot synthesize them. These fats are extremely important for many facets of our health, especially the health of the brain and cardiovascular system.[1] Omega-3 fat is a major structural component of brain cell membranes and the retina – about 60% of the dry weight of the brain is made up of fat, and DHA is the most abundant fat in the brain. [2]
 

As such, DHA is an essential factor in early brain development, and maintaining adequate levels during pregnancy is believed to benefit the child’s cognitive development.[3] The current consensus is that pregnant women should consume at least 200 mg DHA each day to promote normal fetal brain development. Pregnant women are also urged to limit fish consumption because of mercury contamination, which is harmful to the brain of the developing baby.[4] Fish oil or vegan DHA supplements are therefore an attractive option for pregnant women.


In 2009, the results of three randomized controlled trials were pooled and showed that babies given supplemental DHA in formula scored higher on a problem solving test at 9 months of age than babies given control formula. However, there is some disagreement in the literature as to whether DHA supplementation during pregnancy and infancy actually improves cognitive development in the child.[5]


A recently published study in the Journal of the American Medical Association reported an unexpected finding: Pregnant women who took fish oil capsules (800 mg DHA and 100 mg EPA per day) compared to vegetable oil placebo capsules did not have lower incidence of postpartum depression, and their children did not have improved cognitive development at 18 months of age.[6]
Of course, this does not mean that pregnant women shouldn’t bother taking DHA. The developing baby’s only source of DHA for beginning to build its brain tissue is its mother’s dietary intake. DHA supplementation also reduces the risk of preterm birth – a factor known to be associated with compromised cognitive development in the infant and maternal depression.[7]
In reference to the lack of effect on symptoms of depression, the therapeutic effects of omega-3 supplements on depression are due mostly to EPA rather than DHA, according to a recent meta-analysis. [8] I recommend omega-3 supplementation including 1,000 mg of EPA to treat depression – the relatively low dose of EPA used in this trial may therefore be responsible for the lack of effect on depression in this study.


An editorial published in response to the study stated potential reasons why this outcome occurred – these comments also shed light on why there seem to be discrepancies in the medical literature on this subject. One possibility is that the criteria used to measure infant brain development in this study were not sufficiently sensitive to detect small but important differences in cognition in 18-month olds. The criteria used were based on global measures of cognition, and are not designed to detect differences in specific processes such as memory, attention, and problem-solving.[7] As mentioned above, previous studies have seen differences in problem solving in infants given supplemental DHA.[5] Furthermore, there are several cognitive functions that cannot be accurately measured until children reach preschool and school age – the editorial cites a smaller study of fish oil supplementation during pregnancy that found enhanced IQ scores in 4 year olds.[9] I agree that it isn’t possibly to reliably measure intelligence in an 18-month old, and that better results would come from studies that measure cognitive function once the children are in school.


DHA is a vital component of brain tissue, and pregnant women should take at least 200 mg each day to prevent preterm birth and support normal fetal brain development to assure maximum intelligence.

 

References:

1. Yurko-Mauro, K., Cognitive and cardiovascular benefits of docosahexaenoic acid in aging and cognitive decline. Curr Alzheimer Res, 2010. 7(3): p. 190-6.
2. Muskiet, F.A., et al., Is docosahexaenoic acid (DHA) essential? Lessons from DHA status regulation, our ancient diet, epidemiology and randomized controlled trials. J Nutr, 2004. 134(1): p. 183-6.
3. Ryan, A.S., et al., Effects of long-chain polyunsaturated fatty acid supplementation on neurodevelopment in childhood: a review of human studies. Prostaglandins Leukot Essent Fatty Acids, 2010. 82(4-6): p. 305-14.
4. Koletzko, B., I. Cetin, and J.T. Brenna, Dietary fat intakes for pregnant and lactating women. Br J Nutr, 2007. 98(5): p. 873-7.
5. Drover, J., et al., Three randomized controlled trials of early long-chain polyunsaturated Fatty Acid supplementation on means-end problem solving in 9-month-olds. Child Dev, 2009. 80(5): p. 1376-84.
6. Makrides, M., et al., Effect of DHA supplementation during pregnancy on maternal depression and neurodevelopment of young children: a randomized controlled trial. JAMA, 2010. 304(15): p. 1675-83.
7. Oken, E. and M.B. Belfort, Fish, fish oil, and pregnancy. JAMA, 2010. 304(15): p. 1717-8.
8. Martins, J.G., EPA but not DHA appears to be responsible for the efficacy of omega-3 long chain polyunsaturated fatty acid supplementation in depression: evidence from a meta-analysis of randomized controlled trials. J Am Coll Nutr, 2009. 28(5): p. 525-42.
9. Helland, I.B., et al., Maternal supplementation with very-long-chain n-3 fatty acids during pregnancy and lactation augments children's IQ at 4 years of age. Pediatrics, 2003. 111(1): p. e39-44.

 

Vitamin D update: Diabetes, cognitive decline, asthma, and heart attack

Vitamin D is continuing to make news.  Although previously well-known for its effects on calcium absorption and therefore bone health, vitamin D has now emerged as a contributor to many nonskeletal physiological processes, and functions have been attributed to vitamin D in the prevention of cancer, cardiovascular disease, infections, autoimmune diseases, and more. There are vitamin D receptors in almost every cell in the human body, and vitamin D regulates the expression of over 200 different genes. It is not surprising that sufficient vitamin D is crucial to the proper function of so many of our body’s tissues.1

Scientists estimate that 50% of the population of North America and Western Europe has insufficient blood vitamin D levels (as measured by 25(OH)D; sufficient is defined as greater than 30 ng/ml). Although recommended vitamin D intakes remain at only 200-400 IU per day, there is consensus among the scientific community that 2000 IU or more may be necessary for most  people to maintain sufficient blood levels.2

The newest research has found that vitamin D sufficiency is important for preventing type 2 diabetes, cognitive decline, asthma, and cardiovascular disease.

 

 

 

Type 2 diabetes

There is some evidence that vitamin D is involved in insulin secretion by pancreatic beta cells, since insulin secretion is a calcium-dependent process. Vitamin D may also prevent the development of insulin resistance by stimulating expression of the insulin receptor on the surface of cells that use glucose as fuel.3 A recent study performed at Johns Hopkins University School of Medicine on type 2 diabetics found that 91% of the patients were either deficient (less than 15 ng/ml) or insufficient (between 15 and 30 ng/ml) in vitamin D. Furthermore, there was inverse association between vitamin D levels and HbA1c, an indicator of blood glucose levels over the preceding 2-3 months, implying that vitamin D sufficiency contributes to glycemic control in diabetics.4 Vitamin D’s effects are not specific to type 2 diabetes; there is also convincing evidence that vitamin D supplementation during pregnancy and early childhood can reduce the risk of type 1 diabetes, and prospective studies on this topic are ongoing.1,5

Cognitive decline

Vitamin D receptors are present throughout the entire human brain, and genes that are regulated by vitamin D are involved in processes such as memory formation and neurotransmission.6,7 Although previous studies have been inconclusive8, this new data supports a role for vitamin D in maintaining brain health in older adults. 

Asthma

Two recent studies on asthma, one in adults and one in children, has linked vitamin D insufficiency with increased asthma severity.9 Those with 25(OH)D levels above 30 ng/ml had greater lung function, and used less medication.10 A similar study in children also found that lower vitamin D levels were associated with increased asthma severity, and that higher vitamin D levels were associated with reduced odds of hospitalization for asthma.11 Vitamin D’s anti-inflammatory actions or regulation of smooth muscle cell contraction via calcium handling may be the responsible factors. The researchers are currently conducting a trial investigating vitamin D supplementation as a therapeutic option for asthma. Vitamin D is also important for lung development in utero, so maternal supplementation with vitamin D during pregnancy is recommended.12

Cardiovascular disease

There is continually building evidence in the literature that sufficient vitamin D levels protect against cardiovascular disease. Vitamin D deficiency is extremely prevalent among heart attack sufferers – 96% of heart attack sufferers in a recent study were either insufficient (21%) or deficient (75%) in vitamin D. Those with sufficient vitamin D levels are less likely to die from heart attack or stroke.  Vitamin D insufficiency may allow for increased cholesterol uptake by inflammatory cells, which contributes to atherosclerosis.13 A newly published study recorded vitamin D levels at baseline and throughout 6 years of follow-up. At the start of the study, the average 25(OH)D level was 19.3 ng/ml (insufficient). During the trial, about half of the subjects increased their levels to the sufficient range (above 30 ng/ml), and these subjects had significantly reduced incidence of heart attack, heart failure, and coronary artery disease. Some subjects raised their 25(OH)D levels above 44 ng/ml, and they received even stronger protection against cardiovascular disease. Compared to those who reached levels above 44 ng/ml, those whose levels stayed between 10 and 19 ng/ml had a 27% increase in coronary artery disease, a 32% increase in heart failure, and a 59% increase in heart attack incidence.14

Maintaining sufficient vitamin D levels is essential to our health. 

Very few foods naturally contain vitamin D and we cannot rely on sun exposure alone because of indoor jobs, cool climates, and the risk of skin cancer that may arise from adequate amounts of sun exposure to maintain vitamin D levels.   Plus, requirements vary with genetics and skin type greatly effecting Vitamin D production in the skin.  Taking a multivitamin is not the answer because almost all  multivitamins still provide an inadequate amount of vitamin D (400 IU). Favorable levels can be confirmed with a blood test, and supplementation can be adjusted accordingly.   I recommend supplementing with an adequate amount of vitamin D in order to maintain 25(OH)D levels of 35-55 ng/ml. For some people 2000 IU will be sufficient, but others may require more.

References:

1. Hyppönen E. Vitamin D and increasing incidence of type 1 diabetes-evidence for an association? Diabetes Obes Metab. 2010 Sep;12(9):737-43.

2. University of California - Riverside (2010, July 19). More than half the world's population gets insufficient vitamin D, says biochemist. ScienceDaily. Retrieved July 28, 2010, from http://www.sciencedaily.com /releases/2010/07/100715172042.htm

3. Pittas AG, Lau J, Hu FB, Dawson-Hughes B. The role of vitamin D and calcium in type 2 diabetes. A systematic review and meta-analysis. J Clin Endocrinol Metab. 2007 Jun;92(6):2017-29.

4. The Endocrine Society (2010, June 21). Poor control of diabetes may be linked to low vitamin D. ScienceDaily. Retrieved July 28, 2010, from http://www.sciencedaily.com /releases/2010/06/100621091209.htm

5. Zipitis CS, Akobeng AK. Vitamin D supplementation in early childhood and risk of type 1 diabetes: a systematic review and meta-analysis. Arch Dis Child. 2008 Jun;93(6):512-7.

6. McCann JC, Ames BN. Is there convincing biological or behavioral evidence linking vitamin D deficiency to brain dysfunction? FASEB J. 2008 Apr;22(4):982-1001.

7. Llewellyn DJ, Lang IA, Langa KM, et al. Vitamin D and Risk of Cognitive Decline in Elderly Persons Arch Intern Med. 2010;170(13):1135-1141.

8. Annweiler C, Allali G, Allain P, et al. Vitamin D and cognitive performance in adults: a systematic review. Eur J Neurol. 2009 Oct;16(10):1083-9.

9. EurekAlert! Low vitamin D levels associated with more asthma symptoms and medication use. http://www.eurekalert.org/pub_releases/2010-04/njma-lvd041510.php#

Jancin B. Vitamin D Tied to Airway Hyperresponsiveness. Family Practice News. May 1, 2010.

10. Sutherland ER, Goleva E, Jackson LP, et al. Vitamin D levels, lung function, and steroid response in adult asthma. Am J Respir Crit Care Med. 2010 Apr 1;181(7):699-704.

11. Brehm JM, Celedón JC, Soto-Quiros ME, et al. Serum vitamin D levels and markers of severity of childhood asthma in Costa Rica. Am J Respir Crit Care Med. 2009 May 1;179(9):765-71.

12. Litonjua AA. Childhood asthma may be a consequence of vitamin D deficiency. Curr Opin Allergy Clin Immunol. 2009 Jun;9(3):202-7.

13. Washington University School of Medicine (2009, August 25). Why Low Vitamin D Raises Heart Disease Risks In Diabetics. ScienceDaily. Retrieved July 28, 2010, from http://www.sciencedaily.com /releases/2009/08/090821211007.htm

14. Jancin B. CAD Events Less Likely With Normal Vitamin D. Family Practice News, May 15, 2010.

 

Pregnant women are not getting enough vitamin D

Research on vitamin D is exploding, and we are learning that sufficient blood levels of this vitamin are crucial to our health, and also that a significant proportion of the population, including pregnant women, is deficient. Vitamin D is a key factor in fetal bone growth during the third trimester. For pregnant and nursing women, vitamin D insufficiency increases the risk of preeclampsia and also puts their children at risk of impaired growth during infancy and autoimmune diseases during childhood.1

Despite these dangers, vitamin D deficiency is common, affecting up to 50% of pregnant women and breastfed infants.1 Most prenatal vitamins, similar to other conventional multivitamins, contain only 400 IU vitamin D, an amount that is known throughout the scientific community to be inadequate for maintaining sufficient blood levels of vitamin D.

The National Institutes of Health considers 2000 IU to be the daily tolerable upper limit of vitamin D intake, but scientists wanted to know whether higher doses would be safe for pregnant women, and more importantly, whether using higher doses to attain sufficient blood levels of vitamin D would reduce the risk of pregnancy complications.

Researchers tested 400, 2000, and 4000 IU doses of vitamin D in pregnant women starting at 12 weeks gestation. They saw significant differences between groups in blood levels of vitamin D (25(OH)D). In healthy adults, a minimum of 30 ng/ml 25(OH)D is thought to be required for vitamin D to properly exert its many vital functions in the body.2 Consequently, I recommend that levels be maintained in the range of 35-55 ng/ml. The 400 IU group maintained 25(OH)D levels of only about 30 ng/ml, and the 2000 IU group reached 25(OH)D of 42 ng/ml by the end of their pregnancies. The 4000 IU group’s levels reached the optimal range earlier on in pregnancy and remained between 40 and 50 ng/ml for the duration of the study. Since there were no differences in any safety measures, and no adverse events were attributed to the supplements, the researchers concluded that vitamin D supplementation of up to 4000 IU is safe for pregnant women.3

The researchers then looked at pregnancy outcomes – whether the vitamin D affected pregnancy complications such as pre-term labor, pre-term birth, and infection.

The risk of these pregnancy complications overall was 50% lower in the 4000 IU group than the 400 IU group. Women who had complications on average had lower 25(OH)D levels than women who did not have complications. Importantly, neonatal serum 25(OH)D correlated with maternal 25(OH)D, confirming that the additional vitamin D helped to insure that babies were born with sufficient vitamin D levels.4

As mentioned above, I recommend that 25(OH)D levels be maintained in the range of 35-55 ng/ml. These authors recommend serum 25(OH)D levels of at least 40 ng/ml, and therefore supplementation level of 4000 IU according to their results. However, the level of supplementation necessary for individuals to reach optimal serum 25(OH)D levels may vary. Vitamin D needs of individual pregnant women should be assessed by blood test and supplementation should be adjusted accordingly. For some women that may be 2000 IU, but others may require more. I will continue to monitor these studies, and update my recommendations accordingly. 

 

References:

1. Mulligan ML et al. Implications of vitamin D deficiency in pregnancy and lactation. Am J Obstet Gynecol. 2009 Oct 19. [Epub ahead of print]

2. Holick MF, Chen TC. Vitamin D deficiency: a worldwide problem with health consequences.Am J Clin Nutr 2008;87(suppl):1080S– 6S.

3. Wagner CL et al. "Vitamin D supplementation during Pregnancy Part I NICHD/CTSA Randomized Clinical Trial (RCT): Safety Considerations" PAS 2010; Abstract 2630.7.

4. Wagner CL et al. "Vitamin D supplementation during Pregnancy Part 2 NICHD/CTSA Randomized Clinical Trial (RCT): Outcomes" PAS 2010; Abstract 1665.6

MedPageToday: PAS: Vitamin D Cuts Risks of Pregnancy. Michael Smith, North American Correspondent, MedPage Today May 01, 2010

http://www.medpagetoday.com/tbprint.cfm?tbid=19847

Excess iron and copper contribute to chronic disease and aging

Both iron and copper serve vital functions, but as we age excess stores of these metals may build and become toxic. A report from the American Chemical Society1 suggests that iron and copper toxicity are unrecognized but significant threats to public health, in particular for adults over the age of 50.

pennyIron is crucial for oxygen transport and the proper function of several enzymes and proteins. Similarly, copper is also a component of enzymes that catalyze important reactions in several of the body’s cells and tissues. The human body evolved to store excess iron and copper to fuel these vital processes in case of extreme conditions like bleeding or famine, but their accumulation over time may be detrimental because both metals are involved in the production of reactive oxygen species (ROS).

It is now generally accepted that oxidative damage, a byproduct of oxygen-dependent energy production, contributes to chronic diseases and aging.

Oxidation of LDL cholesterol is one of the initial steps of atherosclerotic plaque development. Epidemiological associations between body stores of each of these metals and atherosclerosis have been found, and this is thought to be due to ROS production.2 

Oxidative damage and depletion of the brain’s natural antioxidant defenses are implicated in the neurodegeneration associated with Alzheimer’s disease. Because the brain uses more oxygen and produces more energy than any other organ, it is the most vulnerable organ to oxidative damage. The high iron content of the brain, even higher in those with excessive iron stores, makes the brain even more vulnerable to oxidative stress.3

In people at least 65 years of age who consumed diets high in saturated and trans fats, copper intake was associated with accelerated cognitive decline. Copper bound to cholesterol is also commonly found in the β-amyloid plaques characteristic of Alzheimer’s disease.4

Excess quantities of these metals primarily come from meat, followed by multivitamin/multimineral supplements. Copper in supplements and drinking water is even more toxic than copper derived from food sources.1   

The author of this new report has outlined steps that we can take to limit our exposure to copper and iron, including:

  • Avoiding or minimizing red meat consumption

  • Avoiding drinking water from copper pipes

  • Choosing a multivitamin that does not contain copper and iron. 

Dr. Fuhrman designed his Gentle Care Formula multivitamin/multimineral to be free of potentially toxic ingredients like copper and iron.

 

References:

1. American Chemical Society (2010, January 22). Consumers over age 50 should consider cutting copper and iron intake, report suggests. ScienceDaily. Retrieved January 29, 2010, from http://www.sciencedaily.com /releases/2010/01/100120113553.htm 

Brewer GJ. Risks of Copper and Iron Toxicity during Aging in Humans. Chem Res Toxicol. 2009 Dec 7. [Epub ahead of print]

2. Brewer GJ. Iron and Copper Toxicity in Diseases of Aging, Particularly Atherosclerosis and Alzheimer’s Disease. Exp Biol Med 232 (2): 323. 2007

3. Kidd PM. Neurodegeneration from Mitochondrial Insufficiency: Nutrients, Stem Cells, Growth Factors, and Prospects for Brain Rebuilding Using Integrative Management. Alternative Medicine Review 2005;10(4):268-293

4. Morris MC et al. Dietary copper and high saturated and trans fat intakes associated with cognitive decline. Arch Neurol. 2006 Aug;63(8):1085-8.

Dr. Fuhrman warns: DO NOT take multivitamins or prenatal vitamins that contain folic acid

Folic acid supplementation is dangerous – especially for pregnant women

In a 10-year study,1,2 scientists found that women who take multivitamins containing folic acid increase their breast cancer risk by 20-30%.

Even more alarming are the associations between supplemental folic acid during pregnancy and death from breast cancer,8 and asthma and respiratory tract infections in children.5-6

Read full article

broccoli

Folic acid is the synthetic form of folate, a B vitamin, which is abundant in green vegetables. Folate protects against birth defects known as neural tube defects (NTDs). Pregnant women could safely increase their folate status and prevent NTDs by eating green vegetables, but instead they are instructed to take folic acid supplements, putting them and their children at risk. Folic acid supplements are not a substitute for folate-containing green vegetables – there are inverse associations between maternal vegetable intake and childhood cancers.12-13

Unlike synthetic folic acid, folate obtained from food sources – especially green vegetables – protects against breast and prostate cancer.

There is inverse relationship between dietary folate intake and breast and prostate cancer.14,3 Chemical differences between folate and folic acid translate into differences in uptake and processing of these two substances by the cells in the intestinal wall – excess folic acid in the circulation can occur. Luckily, folate from food comes naturally packaged in balance with other micronutrients and the body regulates its absorption.9

Rich sources of food folate

As a reference point, the U.S. RDA for folate is 400μg. Below is the approximate folate content for a 100-calorie serving.8

Spinach, raw

843 μg

Romaine lettuce

800 μg

Asparagus, cooked

750 μg

Mustard greens, raw

700 μg

Collards, raw

550 μg

Broccoli, cooked

300 μg

Edamame

225 μg

Chickpeas

150 μg

Papaya

90 μg

Orange

70 μg

Blackberries

55 μg

Avocado

50 μg

Sunflower seeds

40 μg

Quinoa, cooked

35 μg

Additional foods listed in full article

Clearly, we do not need synthetic folic acid supplements to meet our daily folate requirements.

Dr. Fuhrman’s Gentle Care Formula Multivitamin does not contain folic acid

Supplemental folic acid has also been linked to prostate cancer3, colorectal cancer4, and overall cancer mortality.7 Because folate is abundant in the nutritarian diet, and synthetic folic acid is so potentially dangerous, folic acid is not included in Dr. Fuhrman’s Gentle Care multivitamin.

Dr. Fuhrman does not recommend prenatal vitamins because of the potentially harmful ingredients, such as folic acid.

Dr. Fuhrman’s special recommendations for pregnant women:

(See full article for references)

 

Vitamins and Selenium Don't Prevent Prostate Cancer

Cancer is a disease. And according to Dr. Fuhrman, eating lots of high-nutrient foods protect against prostate cancer, namely fruits and vegetables, like watermelon, tomatoes, pomegranates, green vegetables, berries and figs. And avoiding harmful foods, like meat and dairy, help reduce men’s risk of prostate cancer. A healthy diet is key! Not just taking supplements and eating crappy food.

That’s why a new study in the Journal of the American Medical Association reveals vitamin C, vitamin E and selenium don’t prevent prostate cancer. Researchers found that 35,533 cancer-free men, in their 50’s, who took selenium and vitamin supplements, several years later had the same risk of developing prostate cancer as men who received the placebo, Health Magazine investigates.

And similar research has shown simply taking vitamins C and E don’t ward off heart disease either.