Green and orange vegetable consumption - an indicator of longevity

No matter how many different dietary theories there are out there, pretty much everyone agrees that vegetables are “good for you”. But how good they truly are has been debated – there are plenty of observational studies linking vegetable consumption to favorable health outcomes, but other studies have made headlines by casting doubt on how powerful plant foods are for preventing disease. The data from these observational studies is often flawed simply because the majority of people in the Western world don’t eat enough vegetables to have a measurable impact on their risk of chronic disease – only about 25% of Americans eat the recommended three one-cup servings of vegetables each day.[1] Also, total vegetable consumption isn’t necessarily an accurate indicator of the healthfulness of one’s diet, since some vegetables are far more nutrient-dense than others. Of course, long-term controlled trials of consumption of a high-nutrient vegetable-based (nutritarian) diet have not yet been published (with the Nutritional Research Project, I aim to fill this gap in the medical literature). Some long-term observational studies, however, do provide clear, high-quality data demonstrating that vegetable consumption is an important factor in chronic disease prevention – a recent study on serum α-carotene levels and risk of death provides such data.

Alpha-carotene is one of over six-hundred different carotenoids, a family of antioxidants that also includes β-carotene, lycopene, lutein, zeaxanthin, and astaxanthin. Carotenoids help to defend the body’s tissues against oxidative damage, which is a natural byproduct of our oxygen-dependent metabolism. [2] Oxidative damage to DNA, proteins, and lipids is a known contributor to chronic disease and an accepted mechanism of aging. The body’s defenses against oxidative damage consist of naturally produced as well as diet-derived antioxidant molecules.

Many prospective studies in the past few years have supported the epidemiologic association between plasma carotenoids and reduced risk of disease and/or death. [3-6] However, these studies didn’t differentiate between carotenoids from food and those from supplements. Carotenoid supplements have failed to duplicate this effect in clinical trials. In fact, supplemental carotenoids are likely to be harmful. A recent meta-analysis of several trials found a 7% increase in mortality risk in subjects taking β-carotene supplements. [7, 8] Also, high serum β-carotene has been associated with decreased lung cancer risk, but β-carotene supplements may increase the risk of lung cancer, especially in smokers.[9] Attempting to duplicate the beneficial effects of carotenoid-rich foods with isolated nutrients is foolish - it completely neglects the contribution of additional and/or synergistic effects of other nutrients contained in those foods.

Beta-carotene is the most widely studied carotenoid, but α-carotene more accurately reflects vegetable intake because α-carotene is not present in most multivitamins and supplements. It is also an excellent marker of high-nutrient vegetable intake, since dark green and orange colored vegetables are the richest sources of alpha carotene. Green vegetables are the highest in overall nutrient density, and of course they are the foods richest in alpha carotene.

This study measured baseline serum α-carotene and tracked deaths in the 15,318 participants over a fourteen-year follow-up period. After controlling for potential confounding factors, the researchers found a significant trend – increasing serum α-carotene associated with decreased risk of death from all causes. Those with the highest serum α-carotene had a 39% decrease in risk of death compared to those with the lowest serum α-carotene. Similar relationships were found between serum α-carotene and risk of death from cardiovascular disease, all causes other than CVD, and cancer.

Serum α-carotene % Decrease in risk of death from all causes
0-1 µg/dl (Reference group)
2-3 µg/dl 23%
4-5 µg/dl (average 4.79 µg/dl) 27%
6-8 µg/dl 34%
≥9 µg/dl  39%

Alpha-carotene itself does provide significant antioxidant benefit –but more importantly α-carotene is a marker of the thousands of additional compounds, working synergistically to keep the body healthy present in green and orange vegetables. [10]

These results suggest that not only quantity of vegetable consumption, but the type of vegetables consumed has a major impact on health. This is the main principle behind the nutritarian diet – eating according to nutrient density. This large, long term study gives much support to the concept of nutritarianism, as many foods high in α-carotene tend to be high in micronutrients overall – the foods that make up the base of the nutritarian food pyramid. And of course keep in mind, even in the highest alpha carotene group in this study, the levels of vegetable consumption as a percent of total calories are likely not nearly as high as in someone following a nutritarian diet. Also, the serum level of alpha carotene in someone following a typical Western diet likely reflects mostly carrot consumption compared to the wide variety of green and yellow vegetables that would be consumed as part of a nutritarian diet, from which further benefits would be expected to accrue from the variety of phytochemicals contained within those vegetables.

Examples of foods with a high α-carotene to calorie ratio[11]:

  • Bok choy
  • Cabbage
  • Red peppers
  • Carrots
  • Swiss chard
  • Green peppers
  • Asparagus
  • Collards
  • Broccoli
  • Winter squash
  • Peas

 

 

 

 

 

Now imagine if such a study was done on people eating the dietary quality I recommend, which would result in levels even much higher than those in the study, and imagine if a diet of this quality was done for more than 10 years and with other synergistic foods, such as mushrooms, onions, berries and seeds. Just imagine...

 

References:

1. State-Specific Trends in Fruit and Vegetable Consumption Among Adults --- United States, 2000--2009. U.S. Centers for Disease Control and Prevention. Morbidity and Mortality Weekly Report September 10, 2010 November 24, 2010]; Available from: http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5935a1.htm.
2. Krinsky, N.I. and E.J. Johnson, Carotenoid actions and their relation to health and disease. Mol Aspects Med, 2005. 26(6): p. 459-516.
3. Lauretani, F., et al., Low total plasma carotenoids are independent predictors of mortality among older persons: the InCHIANTI study. Eur J Nutr, 2008. 47(6): p. 335-40.
4. Akbaraly, T.N., A. Favier, and C. Berr, Total plasma carotenoids and mortality in the elderly: results of the Epidemiology of Vascular Ageing (EVA) study. Br J Nutr, 2009. 101(1): p. 86-92.
5. Ito, Y., et al., A population-based follow-up study on mortality from cancer or cardiovascular disease and serum carotenoids, retinol and tocopherols in Japanese inhabitants. Asian Pac J Cancer Prev, 2006. 7(4): p. 533-46.
6. Ray, A.L., et al., Low serum selenium and total carotenoids predict mortality among older women living in the community: the women's health and aging studies. J Nutr, 2006. 136(1): p. 172-6.
7. Bjelakovic, G., et al., Antioxidant supplements for prevention of mortality in healthy participants and patients with various diseases. Cochrane Database Syst Rev, 2008(2): p. CD007176.
8. Bjelakovic, G., et al., Systematic review: primary and secondary prevention of gastrointestinal cancers with antioxidant supplements. Aliment Pharmacol Ther, 2008. 28(6): p. 689-703.
9. Druesne-Pecollo, N., et al., Beta-carotene supplementation and cancer risk: a systematic review and metaanalysis of randomized controlled trials. Int J Cancer, 2010. 127(1): p. 172-84.
10. Li, C., et al., Serum {alpha}-Carotene Concentrations and Risk of Death Among US Adults: The Third National Health and Nutrition Examination Survey Follow-up Study. Arch Intern Med, 2010.
11. NutritionData.com: Nutrient Search Tool. 2009]; Available from: http://www.nutritiondata.com/tools/nutrient-search.

 

Rocking Out to Food Safety!

Food safety is a serious matter. Between salmonella and E. coli, we’ve got our hands full, but that doesn’t mean we can’t rock and roll! Check out Salmonella and the Pathogens belting out a silly version of "Heartache Tonight” by The Eagles:

 

 

I’m an Eagles fan, so my heart is with the original, but food music is pretty popular nowadays. For example, this funny looking guy can make wind instruments out of carrots, asparagus and broccoli. Clearly, he has way too much time on his hands.

Via SeriousEats.

Image credit: foodsafetymusic

Donkey Boy Goes to Town on a Carrot

Scrubs might be the greatest show on television. In fact, Dr. Cox is my favorite doctor. Now, in this clip the gang is confronted with a carrot devouring donkey boy:

 

 

For more veggie-based hilarity, check out John Legend and Stephen Colbert singing about nutmeg, sweet, sweet nutmeg! Oh, and don’t forget the Christmas pickle.

Image credit: blue1231

On Manager's Special 2.23.09

 

Ripe bananas only $0.75!

 

 

Apples and a pear $1.00.

 

 

And my mom found these baby carrots for $1.50.


Grand total just $3.25. Very cool.

Okay, those bananas are going into smoothies, apples and pears make great snacks and I'm sure my mom will do something cool with the carrots.

Giant Freaking Carrots!

Okay, I’ve had success growing big tomatoes, but a 19-foot carrot. How the heck do you dig it up! Joe Atherton of Mansfield Woodhouse in Nottinghamshire, England, figured out how. He’s the Guinness World Record holder of the longest carrot ever recorded at exactly 19 feet and 1.875 inches. Wow!

Oh, the other carrot was found at a supermarket in Tokyo, Japan. It’s packed with an extra big load of beta-carotene. And can be used to thwart burglars! Bugs Bunny is moaning with ecstasy.

Via Neat O Rama.

FDA Calls Genetically Engineered Animals Cutting Edge...

In a statement last week, the U.S. Food and Drug Administration said genetically engineered animals, not including cloned animals, hold substantial promise for improving public health, i.e. these creatures can enter the food supply, but not before rigorous scientific testing. However, the FDA will not require companies to label that their meat has come from genetically engineered animals, outraging consumer groups. One organization claims the FDA is disregarding consumers' right to choose; CNN investigates.

There’s a bizarre compulsion in this country to futz with what Mother Nature took millions of years to perfect, like do we really need purple tomatoes infused with snapdragon genes or carrots with scorpion parts? I doubt it. Not to mention, an experiment in 2007 showed rats fed genetically modified corn developed signs of kidney and liver disease after 3 months.

And as for cloned meat, it won’t be labeled either and many health experts don’t want it.

Image credit: Ilja

Nutrient-Dense Christmas Goose

Dining on a Christmas goose is not exactly part of a vegetable-based diet. But don’t fret. You can have your veggies and your goose. This chef just needs some squash, carrots, toothpicks and a sharp knife. And presto, twin veggie geese!

I’m tempted to try this myself. But given my artistic abilities it’d probably turn out to be a lame duck. Stop by tomorrow for one last holiday post. Quack, quack.