Ask the Experts

Q: Whats the safe level of daily vitamin D? Is it different for older...

Answer :The recommended intake of vitamin D-but not the safe limit-does increase with age: The Institute of Medicine has set the daily adequate intake for adults ages 19 to 50 at 200 IU of vitamin D, for ages 51 to 70 at 400 IU, and for those older than age 70 at 600 IU. Many experts, however, argue that those levels should be raised, and research has shown that 800 to 1,000 IU daily may…

Q: Is buckwheat a grain or is it actually a seed? I have it...

Answer : According to the Whole Grains Council www.wholegrainscouncil.org, buckwheat is neither a grain nor, despite its name, a relative of wheat...

Q: Ive read that calcium should be taken/ingested periodically during the day, as only...

Answer :Bess Dawson-Hughes, MD, professor of medicine at Tufts and chief of the Bone Metabolism Laboratory at the Jean Mayer USDA Human Nutrition Research Center on Aging, responds: Calcium is better absorbed if taken in doses of 500 milligrams or less. So 1,000 milligrams as a supplement should be taken in doses of 500 milligrams twice daily.…

Q: I am enclosing an article from a local newspaper warning people to avoid...

Answer :The article in question warns about the dangers of mercury and other contamination in tuna and other fish, concluding that Fish is anything but health food. While its wise to be wary of potential toxins in fish, the consensus of scientists who have examined the evidence-as opposed to taking an ethical stand, as PETA does, that animals are not to eat-is that fish is in fact one of the healthiest foods you can include…

Q: How can I keep from overeating during the holidays?

Answer : Helen Rasmussen, PhD, RD, an instructor at Tufts Friedman School, enlisted Laura Ficker, a masters candidate at the school, to offer these holiday tips:

Q: Is canned spinach just as good as fresh spinach to protect my vision?

Answer :Scientists believe that eating lutein, a nutrient found in green vegetables such as spinach, kale and broccoli, may help prevent eyesight deterioration. It is believed that lutein protects against cataracts and agerelated macular degeneration (AMD), both of which cause loss of vision. According to Allen Taylor, PhD, director of the Laboratory for Nutrition and Vision Research at Tufts Jean Mayer USDA Human Nutrition Research Center on Aging, the lutein content of spinach is not…

Q: Is much of the omega-3 lost when the skin of the salmon is...

Answer :According to Alice H. Lichtenstein, DSc, director of the Cardiovascular Nutrition Laboratory at Tufts Jean Mayer USDA Human Nutrition Research Center on Aging, much of salmons healthy omega-3 fatty acids lie just under the skin. Comparing total omega-3s for the same variety of salmon in different preparations using the USDAs Nutrient Database, salmon without the skin contains only 39% to 64% of the omega-3s in the same portion of salmon with the skin. But…

Q: Do egg yolks really differ from egg whites in terms of raising bad...

Answer : A Yolks contain the fat and cholesterol in an egg, in addition to protein, vitamins and minerals.

Q: We always have a bounty of fresh fruit-more than we can eat before...

Answer :Healthletter recipe consultant Patsy Jamieson replies: To freeze fresh fruit without sugar, peel and pit, if necessary, or rinse and pat dry. Slice or cut fruit into bite-sized pieces. Spread on a tray, cover and freeze until solid. Transfer to a plastic food storage bag, remove air from bag, seal and label. Freeze for up to eight months. To prevent peaches, bananas and mangos from turning brown, coat with lemon juice or an anti-browning…

Q: I have been told that the sugar substitute Splenda is unhealthy due to...

Answer :Its true that Splenda is made using chlorine, which sounds scary; the sugar industry warns that youre actually eating chlorine when consuming sucralose, the chemical sold as Splenda. Plain sugar is transformed into sucralose by substituting three chlorine atoms for hydrogen, creating a substance that is not digested by the body-so its effectively caloriefree- and thats 600 times sweeter than sugar. (Packaged Splenda also contains dextrose and maltodextrin as bulking agents.) But theres no…