Straightening Out 4 Nutrition Brain-Benders
by Althea Zanecosky
The science of nutrition is constantly evolving. As researchers learn more about a food or nutrient, dietary advice changes. But sometimes there can be conflicting information. Here are four seemingly contradictory nutrition factors and how to make sense of them.
1. Vitamin D
The good news: Short amounts of sun exposure produce enough vitamin D to build and maintain healthy bones and may have anti-cancer benefits.
The bad news: Exposure to sunlight causes skin cancer.
What the science says: Vitamin D signals the body to absorb more bone-building calcium from foods. So choose foods high in Vitamin D milk and fish. If recommended by your doctor, take a daily multivitamin that contains Vitamin D.
Since the most powerful source of vitamin D is the sun, make the most of it by spending some time outdoors every day. Some experts now say it’s a good idea to spend 15-20 minutes in the sun and then apply a screen with sun-protection factor (SPF) of 15 or higher. However, following this approach requires keeping track of the time to avoid unhealthy, unprotected sun exposure.
Experts recommend that you regularly protect your face, ears, neck, and the backs of hands, as these spots are where skin cancers usually develop first.
The good news: Eating fish rich in omega-3s can improve heart health.
The bad news: Some types of fish contain high levels of mercury, a toxin.
What the science says: The Food and Drug Administration and the Environmental Pro-tec-tion Agency issued an advisory recommending that pregnant or nursing women and young children avoid intake of high-mercury fish species, such as swordfish, king mackerel, tilefish, and shark. This is because high mercury levels can cause developmental issues in young children.
But according to a survey, two-thirds of Americans believe the risk applies to everyone, not just expectant mothers and children younger than age 6. Actually, everyone else can focus on the fact that eating fish can help reduce their risk of stroke and heart attack. They can consume the recommended two 6-ounce servings of fatty fish per week.
For anyone seeking to avoid mercury, stick with fish species that are low in mercury but high in omega-3s salmon, canned light tuna, pollock, flounder, sole, herring, shrimp, and sardines.
For more info: www.cfsan.fda.gov/~dms/admehg3.html
3. Organic Foods
The good news: Recent reports indicate that organic fruits and vegetables are less likely to contain pesticide residues than conventional food.
The bad news: Organic fruit and vegetables may be healthier for the dinner table, but not necessarily for the environment. New studies conclude that the environmental impact (greenhouse gasses and energy costs) of transporting organic foods may cancel out the benefits of growing it.
What the science says: Organic and conventional food must meet the same quality and safety standards. Organic food differs from conventionally produced food simply in the way it is grown, handled and processed. There is no scientific evidence to suggest that it is more nutritious or safer than conventional food.
According to the National Research Council, the traces of pesticides left on conventionally grown products are unlikely to cause increased risk of cancer.
If fruits and vegetables are properly washed, most of the chemicals can be removed. So focus on freshness and taste. In general, people tend to find that the fresher a food is, the better it tastes, regardless of how it was produced.
And when comparing organic and regular milk, there is no difference in pesticide levels. The most recent FDA data available indicate that all of the milk tested was found to be free from pesticide residue.
For more info: www.ams.usda.gov/nop/Consumers/brochure.html
The good news: The average American eats the equivalent of 20 teaspoons of sugar a day and sugar substitutes can help people enjoy the sweet taste in foods without the calories. This can be helpful to peple who are diabetic, losing or maintaining weight and in the prevention of tooth decay.
The bad news: The artificial sweetener aspartame is used to sweeten many prepared foods, including beverages, yogurt, and pudding. Aspartame is also used in low-calorie tabletop sweeteners. It has come under fire from individuals who suspect there is link between the sweetener and brain tumors and other serious disorders.
What the science says: The FDA stands behind its original approval of aspartame and subsequent evaluations have shown that the product is safe. A very small segment of the population (those with the genetic disorder phenylketonuria or PKU) is sensitive to one of the sweetener’s byproducts and should restrict intake.
The FDA, the Joint Expert Committee on Food Additives (JECFA) of the World Health Organization, the Scientific Committee for Food of the European Community and regulatory agencies in more than 100 countries have reviewed aspartame and found it safe for use.
The American Medical Association, the American Dietetic Association and the American Diabetes Association also have found aspartame safe.
Scientific studies have shown that children handle aspartame the same way as adults, so this sugar substitute can be safely incorporated as part of a healthy diet for children.
For more info: www.ific.org/publications/brochures/aspartamebroch.cfm
Althea Zanecosky is a Philadelphia registered dietitian and national spokesperson for the American Dietetic Association.