Long Life from Agriculture

When scientists compared the diets of 100 breast cancer patients with those of 175 healthy women, they concluded that with a higher score on the whole-food plant-based index (if one merely doubled the proportion of plants in the Standard American Diet), one would reduce the likelihood of developing breast cancer by more than 90 percent.

Long Life from Agriculture

Probably the least controversial advice in nutrition science is the recommendation to eat more fruits and vegetables, which means: Eat more plants. How much longer might you live if you eat more fruits and vegetables? Someone who eats five servings of fruits and vegetables a day could live seven months longer than someone who eats only two servings. Consuming only one serving daily could mean the loss of a year and a half. With only a half serving, it might be two years less, and if you don’t eat any fruits or vegetables at all, that could cost you three years of life. So for someone eating unhealthily enough, even one serving of fruit a day, for example an apple, could mean a difference of 19 months between life and death. A daily salad could amount to years on this planet.

In contrast, the potential lifelong harm from pesticide residues on those fruits and vegetables is estimated to take only a few minutes from the life of an average person. So while there are many reasons to choose organic produce, worries about pesticide residues should not keep us from stuffing ourselves with as many fruits and vegetables as possible.

The study that looked at the effect of fruits and vegetables in specific amounts on life expectancy focused mainly on people over 50 and 60. Is it too late if we’re over 70? Apparently not. Women over 70 with the most carotenoid phytonutrients in their blood survived the next five years with twice the probability of women with the lowest levels; they may have been able to double their survival odds simply by eating more fruits and vegetables. A study from Taiwan showed that participants could lower their risk of death by about 10 percent with fruits and vegetables costing half a dollar a day. A pretty good deal. Imagine there were a drug that reduced mortality by 10 percent—and had only positive side effects. How much do you think the pharmaceutical companies would charge for it? Probably more than 50 cents.

Food from the Bottom of the Food Chain

When you draw from the very bottom of the food chain with a plant-based diet, you have another advantage in the modern world: You are exposed to fewer industrial toxins that accumulate more and more (bioaccumulate) the higher up the food chain we go. In the video see.nf/eatlow, I examine the role of these toxins in the aging process and disease, for example polychlorinated biphenyls, dioxins, and long-banned pesticides like DDT. Studies of toxins in the breast milk of vegetarians from more than 40 years ago found that their average levels of some toxins were 50 to 100 times lower than the national average. In fact, for six of the seven toxins tested, there was no overlap. The highest value in a vegetarian was lower than the lowest value in the general population. Lower toxin levels could partly explain why those who eat plant-based are less likely to develop a form of cancer.

Based on dioxin contamination alone, the Department of Agriculture calculated that American children who eat meat take in more each day than the amount considered safe. Surprisingly, the differences in toxin contamination between organic meat and conventionally produced meat were minimal, as I show in see.nf/organicmeat. In fact, one could exceed the acceptable levels even if one ate only half as much meat as the average American per-capita consumption, organic or not.

So what can we do to expose ourselves less to these toxins? Eat foods high in fiber, because the fiber can bind some of the toxins and possibly carry them out of our bodies. We can exercise, because toxin levels are lower in physically active people, perhaps due to sweating or stimulation of detoxifying enzymes or because the bile is working harder. When we prepare meat, we can trim off fat and trim and drain off even more fat after cooking, although a recent review, in view of current contamination levels, concluded that “meat consumption should generally decrease significantly, as much and as soon as possible.”

The Vegetarian Achilles’ Heel

The world’s largest association of nutrition professionals, the Academy of Nutrition and Dietetics, is unequivocal about this topic in its current position paper: Plant-based diets are not only “appropriate for all stages of the life cycle,” but may also “provide health benefits in the prevention and treatment of certain diseases.” (I have the honor to announce that the Academy points its readers to my website NutritionFacts.org as a reliable source.) As the emeritus dean of the School of Public Health at Loma Linda once said at a nutrition conference: “Attitudes toward vegetarian nutrition have shifted from mockery and skepticism, to condescending tolerance, to gradual and sometimes grudging acceptance, and now it is being applauded.”

When comparing the quality of various popular dietary patterns and diets, Dean Ornish’s plant-based diet achieved the highest score, and the Atkins diet, with its extreme carbohydrate reduction, the lowest. When they applied different index systems for diet quality, the researchers noted that the dietary patterns ranked higher the more plants were eaten. Although with a plant-based diet one leaves out entire food groups, ironically one takes in more nutrients. One study found that people who eat plant-based took in more of almost every nutrient—more fiber, more vitamins A, C, and E, more of the B vitamins thiamin, riboflavin, and folic acid, and more of the minerals calcium, magnesium, and iron. That should not surprise us. The editor-in-chief of the Journal of the American Dietetic Association wrote: “What could be more nutrient-dense than a vegetarian diet?”

These days, the most extensively published cases of classic nutrient-deficiency syndromes are people who follow extreme diets, like the military service member who was hospitalized with a muscle tear due to scurvy. He reported eating only skinless chicken and candy bars. Ironically, one of the healthiest ways of eating—an exclusively plant-based diet—is also the most dangerous, because it lacks the vital vitamin B12.