Confused about what to eat? You are not the only one! Even I get frustrated with the changing landscape. One week medical reporters tout the benefits of taking a vitamin; the next week they tell us it does no good.
To help resolve some of this confusion, the Tufts University Friedman School of Nutrition Science and Policy gathered experts to speak at a conference held in Boston. Here are some highlights about nutrition confusion that might be of interest to you.
Assuming you are health-conscious, you likely want to know if you should avoid foods such as eggs, salt and sugar. And you may also want to know if you should take supplements such as fish oil, calcium and vitamin D. While those seem like simple questions, the answers are difficult because we all have genetic differences that impact our nutrient needs. For example, salt can raise blood pressure in one athlete, but make no difference in another. Hence, genetic variation skews the research results and ensuing recommendations.
Within our lifetime, genetic testing will offer personalized answers regarding who should or should not eat such things as salt. But genetic testing also raises concerns. That is, if you tell an athlete he is salt-sensitive and his blood pressure will rise if he eats salt, he will likely be inclined to cut back on his salt intake. But if you tell him salt has no effect on his blood pressure, will he abandon all discretion and consume extraordinary amounts of salt that create other health problems? We do not yet know if genetic testing is a wise way to resolve nutrition confusion!
Meaningful nutrition studies are very difficult to produce. Good studies need to explore, for example, the effects of different doses of a vitamin over a long period of time in a variety of people, including large numbers of men, women, children, seniors, athletes, whites, Africans, etc.. Such studies are not only very expensive but also tough to fund. Food companies don’t reap profits from funding such research because they cannot patent foods. Drug companies, in comparison, can get patents and make huge profits once a drug is proven effective.
Unlike drug studies in which the subjects are drug-free until they take the drug, nutrition studies use subjects that already have lots of vitamins in their bodies. Creating a baseline deficiency in each subject would be unethical. Hence, nutrition research can only contrast a high vitamin intake with a low intake. To determine the thresholds at which a vitamin creates desired (or undesired) effects can take weeks or months--and lots more money.
Nutrients Work Synergistically
It’s hard to know what to study. For example, you may want to know if you should take a calcium supplement to keep your bones strong and reduce your risk of breaking a bone. Studies that look at just calcium supplementation (without vitamin D) indicate calcium does not reduce bone fractures. But research with calcium plus D suggests improved bone health; calcium works synergistically with vitamin D. Also note, calcium and other nutrients have differing effects at different intakes. It’s hard to know at what level the nutrient is most effective and at what level it offers no additional benefits.