The World's Healthiest Foods

Foods versus supplements, why foods are better.

Introduction

In the past 50 years, Americans have increasingly relied on the use of supplements as the magic bullet to optimal health. A number of recent studies suggest that not only do whole nutritionally dense foods provide more benefits than isolated nutrients, but the unnaturally high doses of single nutrients supplied by supplements, by upsetting the integrated balance of active compounds found in whole foods, may actually induce detrimental effects on health.

Whole foods contain a wide array of nutrients including not only well known vitamins and minerals, but dozens of other biologically active compounds-all inter-related in a complex system supportive of the life of the plant or animal from which the food was derived. The more research is done, the more complex this life-giving nutrient web is revealing itself to be. Supplements are fragments of this web, artificially isolated from the whole of interlocking parts within which they do their work in living systems. Just as their name implies they are designed to supplement a healthy diet and provide insurance that your nutritional needs are being fulfilled. They are no substitute for a healthy whole foods diet.

Real Life Complexity versus Supplement Simplicity

A whole foods diet contains a great diversity of phytonutrients-some set the stage for the activity of others or work synergistically with them, while some neutralize or balance the effects of others. When we take a supplement, we're often ingesting a single nutrient in a much larger amount than would be obtained from food, plus the supplement may be a synthetic product that is not bio-identical to the natural form of the nutrient. Even isolating one nutrient normally found in the diet, then artificially boosting it, may have unwanted consequences.

Insofar as the research goes, the whole food rather than supplement argument is, in large part, a question of complexity versus simplicity. Researchers cannot cope with the astounding interactive complexity of hundreds of nutrients found in whole foods, so they are forced to zero in on one, or at most, a couple of nutrients.

According to Godfrey P. Oakley, professor of epidemiology, Emory University's Rollins School of Public Health, "It's really tough to know what's in food, but you can know what's in a pill…There were relationships between people eating fruits and vegetables, so they went after this one specific ingredient. It was a lab-based hypothesis chasing human effects." Oakley adds, however, that in instances where a medicinal amount of a nutrient is warranted, supplements do have dose on their side. "You almost can't eat enough nutrients in plants to get your blood levels to where they should be."

Charles E. Elson, a University of Wisconsin at Madison nutritionist, agrees that it's impossible to consume the high doses sometimes recommended for medical intervention in diseases such as cancer, from foods. However, Elson thinks that supplement advocates have oversimplified the issue: "People look at fruits and vegetables, take the prominent compound, and say that's responsible."

Elson suspects that the cumulative interactive effect of the multitude of active compounds found naturally in fruits and vegetables can be more effective than supplements, which, in comparison, go it alone. Currently, instead of focusing on one micronutrient, Elson is attempting to analyze the cumulative, synergistic effects of many isoprenoids-a group of phytonutrients, including lycopene, whose origin is the mevalonic acid pathway-and which, he suspects, account for much of the anti-cancer effects of fruits and vegetables.

Lycopene, whose most well publicized source is tomatoes, is being touted by some as a cancer-preventive supplement, despite the fact that the data supporting such a belief is drawn from epidemiological and population studies of patterns of food consumption, not on the supplemental use of lycopene.

The Harvard study that put lycopene in the public limelight reviewed the eating patterns of nearly 48,000 men and showed that eating tomato sauce a couple of times a week lowered prostate cancer risk. Research focusing only on lycopene has yielded conflicting results, but when investigators have calculated the amount of lycopene consumed daily from foods, men whose average intake was 19 milligrams a day were found to have a 16% lower risk of prostate cancer than men who took in 3 milligrams of lycopene daily.

The reduction in prostate cancer risk was even greater when tomato sauce intake was considered. Men who ate two or more servings of tomato sauce each week were 23% less likely to develop prostate cancer during the study period than men who ate less than one serving of tomato sauce each month. Could it be possible that lycopene is simply a marker-the tip of the cancer-protective phytonutrient iceberg-and not the whole reason why tomatoes are beneficial?

Similarly, studies on heart patients who have taken vitamin E supplements have had varied results, but when the nutrients are consumed as part of a whole foods diet, the results are consistently beneficial. An observational study of 85,000 nurses found that the risk of heart disease was lowest in women with the highest dietary intake of vitamin E, and a second study of 39,000 males revealed similar results.

Whole Foods, But Not Supplements, Consistently Protect Against Disease

Literally hundreds of epidemiological studies have looked at the relationship between whole foods and chronic diseases such as cardiovascular disease, diabetes and cancer. Eating more whole foods has consistently been shown to result in decreased incidence of disease. Those individuals eating the diet that contains the most fresh vegetables, fruits, legumes, nuts, seeds, and whole grains are always in the group found to have the lowest risk, whatever the disease.

A Whole Foods versus Refined Foods Diet

Inconsistencies in epidemiologic findings relating grain fiber to chronic disease can be explained by distinguishing between studies that use nutrient-rich whole grains, which retain their outer layers where their fiber and phytonutrients are concentrated, versus those using nutrient-poor refined grains. Whole grain fiber consumption is associated with a reduced mortality risk in comparison to a similar amount of refined grain fiber.

In the Iowa Women's Health Study, 11,040 postmenopausal women consumed the same total amount of grain fiber, but differed in the proportion of fiber they consumed from whole versus refined grain. These women were followed from 1986 through 1997, and when the data collected was analyzed, it was found that those women who consumed the majority of their fiber from whole grains were much less likely to die from cardiovascular disease than their counterparts eating refined grains.

Specifically, those women who consumed an average 4.7 grams of fiber from whole grains along with another 1.9 grams of fiber from refined grains in their 2,000 calorie diets had a 17% lower mortality rate compared to women who consumed predominantly refined grain fiber: 4.5 grams of fiber from refined grains and only 1.3 grams of fiber from whole grains per 2,000 calories.

Another study of 12 women compared the benefits of a whole foods diet to a refined foods diet and demonstrated the positive effects of a phytonutrient rich diet on lipoproteins, antioxidant defenses and colon function.

In this trial, 12 women with high cholesterol followed a refined-food diet for four weeks after which they immediately switched over to a whole foods diet. At the end of each four week diet, the women's fasting bloods levels of cholesterol and triglycerides were measured along with their fasting levels of antioxidant enzymes. Although both diets provided the same amount of calories and fat, the women ate 61% less saturated fat while on the whole foods diet and their intake of dietary fiber, vitamin E, vitamin C and carotene intakes were 160%, 145%, 160% and 500% more, respectively, than the refined-food diet period.

Not surprisingly, with the increase in fiber, colon function improved on the whole foods diet, which also caused a drop of 13% in total cholesterol, 16% in LDL-C (the most dangerous form of LDL cholesterol). In addition, blood levels of two antioxidants the body produces internally when needed to defend against free radical attack dropped precipitously: superoxide dismutase decreased 69%, and glutathione peroxidase dropped 35%.

Whole Foods Protect against Cardiovascular Disease

In three of the largest, most significant studies that have looked at the relationship between diet and cardiovascular disease-the DART study, the GISSI trial, and the Lyon Heart Study-a whole foods diet consistently and significantly reduced cardiovascular disease risk and mortality.

According to a recent news roundup in the British Medical Journal, the combined evidence of a number of large population-based surveys suggests that for every additional portion of fruit or vegetables eaten, the risk of getting heart disease is reduced by 4%. In one population study, postmenopausal women who ate 10 daily servings of fruit and vegetables lowered their risk of heart attack by 40%.

In the Lyon Heart Study, those following the simple guidelines of increasing their consumption of vegetables, fruit, whole grains and legumes, while decreasing their consumption of saturated fat and eating healthy fats such those in olive oil, nuts and seeds, were found to have dropped their risk of death from cardiovascular disease by an amazing 70% after 27 months. And another recent study found that just eating a handful of nuts each day translates into a 30% reduction in cardiovascular disease risk.

The DASH (Dietary Approach to Stop Hypertension) study demonstrated that a higher intake of whole grains, fruits and vegetables can lower blood pressure. In this trial, a whole foods diet produced an average drop of systolic and diastolic blood pressure of 12mm/6mm in a group of individuals with moderately elevated blood pressure.

Why are all these studies producing such consistently positive results? Here are just a few of the reasons:

With all these beneficial actions, it's not surprising that epidemiological studies all indicate that a whole foods diet protects against cardiovascular disease.

Whole Foods Protect against Arteriosclerosis

A study still in progress, and hopefully the first of many to focus on whole foods, may be demonstrating that whole foods can significantly reduce the progression of atherosclerosis. For almost three years, Dr. Mark Houston, Associate Clinical Professor at Vanderbilt School of Medicine and Director of the Hypertension Institute in Nashville, has been following a group of 50 cardiovascular patients, tracking a hallmark of the progression of cardiovascular disease-the amount of calcium being laid down in their arteries.

"Statistically, calcium deposition as measured by EBT scores goes up about 50% per year, but the data on our study subjects, while not yet complete, looks much more promising. Study subjects have made no other lifestyle changes other than consuming two products made from concentrated whole foods-Juice Plus and Vineyard Plus."

Looking at the preliminary data, Dr. Houston is very encouraged. "If concentrated whole foods products will do this, then we will broaden our approach in cardiovascular treatment to emphasize a whole foods diet," says Houston.

Houston became interested in a whole foods approach to atherosclerosis when his review of the epidemiological literature clearly showed that whole foods did reduce the incidence of cardiovascular disease, but when he looked for the prospective clinical trials that had proven the benefits of whole foods, he found none. A medical pioneer who, in addition to his clinical work is also Editor-in-Chief of the Journal of the American Nutraceutical Association, Dr. Houston decided to do his own prospective trial. He's measuring not only calcium deposition, but also a wide array of indicators of oxidative stress that the latest research shows clearly impacts cardiovascular disease. Houston hopes to wrap up the study by the end of 2003. Initial study publication will report the calcium EBT scores, then, as the wealth of data he is gathering is analyzed, we can look forward a number of articles presenting the correlations between whole foods consumption and reductions in oxidative stress.

Whole Foods Protect against Cancer

Bruce N. Ames, PhD, the renowned U. C. Berkeley nutritionist, reports that more than 200 epidemiological studies indicate that a diet high in fruits and vegetables can reduce cancer risk. A whole foods diet is richly endowed not only with all the well known vitamins and minerals, but also with literally hundreds of phytonutrients whose benefits researchers are just beginning to uncover.

The following provide just a few examples:

Whole Foods Protect against Diabetes

A whole foods' diet also provides well-established benefits for persons with diabetes. In addition to its high levels of anti-inflammatory antioxidants and phytonutrients, which lessen the damage that high blood levels of glucose would otherwise cause, the excellent supply of fiber provided by a whole foods diet slows digestion, lowering insulin requirements, providing better control of blood glucose, and reducing blood cholesterol levels. This combination of benefits is so powerful that the Nurses Health Study indicates a whole foods diet may be the most successful treatment available for managing onset of the insulin resistance that characterizes early stage Type 2 diabetes.

Supplements-Not a Magic Bullet for Good Health

Looking at all the studies that have investigated a relationship between nutrition, heart disease, cancer and diabetes, about two-thirds have focused on individual nutrients (e.g., beta carotene, lycopene, vitamins E and C). The studies using a single or even several nutrients have produced a good deal of controversial and conflicting data.

Synthetic Vitamin E Increases Stroke Risk, Synthetic Beta-Carotene Increases Lung Cancer Risk

One highly publicized example of unpalatable data on the use of supplements is the Alpha Tocopherol Beta Carotene Trial. In this randomized study, 29.133 Finnish male smokers were divided into three groups and followed for a period of up to eight years. One group received placebo, a second was given synthetic beta-carotene, and the third was treated with dl-alpha tocopherol (a synthetic form of one of the four fractions of vitamin E). This study made headline news when, not only did the supplements provide no benefit, but an unexpected increase in the risk of fatal stroke was identified in the vitamin E group, and treatment with synthetic beta-carotene actually lead to a jump in the number of deaths linked to lung cancer.

Other supplementation trials using beta-carotene have also found an increase, rather than a decrease, in lung cancer risk. In a 12 year follow up study of participants in the CARET (beta-Carotene and Retinol Efficacy) Trial, investigators used data from food frequency questionnaires to examine how compounds in fruits and vegetables affect lung cancer risk. What they found was that fruit and vegetable consumption did provide a reduction in lung cancer risk-but only to those in the placebo group-those who were not given the beta-carotene and retinyl palmitate supplements. The researchers concluded: "This report provides evidence that plant foods have an important preventive influence in a population at high risk for lung cancer. However, persons who use beta-carotene supplements do not benefit from the protective compounds in plant foods."

Supplemental Vitamin E Causes Drop in Bneficial HDL

Vitamin E, along with vitamin C, beta-carotene, and selenium also caused problems in another cardiovascular treatment trial. In this study, a combination of niacin and the drug simvastatin reduced clinical cardiovascular events by 90%, but when the antioxidant supplement was added, the rise in beneficial HDL seen with niacin-simvastatin therapy was much lower. Similarly, studies on heart patients who have taken vitamin E supplements have had varied results, but when the nutrients are consumed as part of a whole foods diet, the results are consistently beneficial. An observational study of 85,000 nurses found that the risk of heart disease was lowest in women with the highest dietary intake of vitamin E, and a second study of 39,000 males revealed similar results.

Carotinoids, Supplements and Breast Cancer

Breast cancer may be another case in which a carotenoid-rich diet is protective while the use of certain supplements is not. In patients with breast cancer, tumors that contain estrogen receptors (ER+ breast cancer) are associated with a better response to hormone therapy and improved survival compared to tumors that do not have estrogen receptors (ER- breast cancer). When 142 women diagnosed with breast cancer were evaluated, it was found that their odds of being ER+ increased along with their number of breast fed babies and consumption of green and yellow vegetables, particularly foods rich in carotenoids. On the other hand, their likelihood of being ER+ decreased in relation to how many years they had taken oral contraceptives and their intake of preformed vitamin A. In a second study of older women with breast cancer, women with higher blood levels of lutein from dietary sources, and women not using beta-carotene supplements were also more likely to be ER+.

The Effects of Smoking, Consuming Alcohol and Beta Carotene Supplements on Colon Polyps

In a study, just published in the May 21, 2003 issue of the Journal of the National Cancer Institute, beta-carotene supplementation has again been proven harmful for both smokers and those who consume more than one serving of alcohol a day. In this study, researchers wanted to see if beta-carotene, when taken by individuals who smoke and consume alcohol, would also promote colon cancer.

The study, a double-blind, placebo-controlled trial, involved 864 people who had had colon polyps removed (colon polyps are benign growths that can turn cancerous). Subjects were divided into four treatment groups. One group received beta-carotene (25 mg) alone, a second group received beta-carotene along with vitamins C (1000 mg) and E (400 mg), a third group was given vitamins C and E, and the fourth group got placebo pills. The four treatment groups were sub-divided into non-smokers, smokers, and those who drank alcohol.

After one year and four years, all study participants were checked for recurrence of colon polyps. A total of 707 subjects completed the study. When the data was evaluated, it was found that people who took beta-carotene supplements and smoked and drank more than one alcoholic beverage a day were twice a likely to have a colon polyp recurrence as those who were given placebo. Individually, smoking or drinking also promoted polyp recurrence with beta-carotene supplementation, although not as much as both combined. On the positive side, in subjects who did not smoke or drink, beta-carotene supplements reduced the risk of polyp recurrence by 44%.

How can an antioxidant nutrient like beta-carotene promote cancer?

In addition to the issue that synthetically produced vitamins are not identical to their natural counterparts and therefore cannot be expected to produce identical results, even when naturally bio-identical supplements are used, other recent research suggests that the unnaturally high doses of single nutrients provided may cause unwanted effects. Marvin Legator, professor of preventive medicine and community health at the University of Texas Medical School at Galveston, and colleagues from Bologna, Italy, have shown that, in rat lungs, high doses of beta carotene increase levels of carcinogen-metabolizing enzymes. In non-smokers, these agents might be helpful or at least harmless, but when they react with compounds in tobacco smoke, the resulting chemicals actually promote cancer.

Legator cautions supplement use should be carefully considered because not only beta-carotene, but many nutrients can increase these enzymes. In whole foods, nutrients are found in a balanced matrix, but isolated micronutrients-or fractions of micronutrients such as the alpha tocopherol fraction of vitamin E that lowered beneficial HDL-are not and could have analogous unintended effects.

CONCLUSION

According to an April 2003 WHO/FAO Expert Report, chronic diseases resulting from poor diet contributed to 59% of the 56.5 million deaths worldwide and nearly half the burden of global disease in 2001. Statistics from the NCA in Bethesda Maryland, show that only 23% of American adults eat at least five daily servings of fruit and vegetables, and only 4% of men consume nine servings. About 33% of the US population eats only two servings and another 4% eat even less than that.

Research is showing time after time that the beneficial effects of a diet composed of whole, unrefined foods cannot be matched by a diet based on refined foods, and expecting a handful of supplements to bridge the gap is simply not realistic. Whole grains, dark green and yellow/orange vegetables and fruits, legumes, nuts and seeds, contain high concentrations of antioxidant phenolics, fibers and numerous other phytonutrients that work together to offer protection against many types of chronic disease.

Practical Tip

Take the advice of the World Health Organization and eat a diet abundant in fresh whole fruits and vegetables and low in foods that are high in saturated fats and sugars, and combine it with an active lifestyle to fight chronic diseases including obesity, cancer, cardiovascular diseases and diabetes.

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