DEAR DR. BLONZ: In my new apartment, I am living with a group that primarily eats raw foods. Their explanation is that "cooking removes the vitamins and minerals." These are my friends, so while I detect a slight bit of sanctimony, there is no serious rejection of the fact that I am an omnivore. Is eating nothing but raw foods, or even mostly raw foods, a good idea? One of my roommates says her new diet is really helping her lose weight. What are the pluses and minuses? -- S.T., Oakland, California
DEAR S.T.: Diets that strictly limit what you can eat can result in weight loss simply because you are paying closer attention to the foods you select. When you stick to raw, you definitely limit the types and amounts of foods you can eat. As for whether a raw food diet is a good idea, it depends on how it is done.
First, let's add some perspective to any blanket statement that cooking removes vitamins and minerals. Minerals are not affected at all, and while the levels of a few vitamins are reduced by heat (notably vitamin C, thiamine and folic acid), most are not affected. Cooking can actually help make other nutrients more bioavailable. Proper cooking also makes certain foods easier to digest. The idea that cooking destroys certain vitamins is not a serious issue if the food involved is not the main source of that nutrient. We get our vitamin C, for example, from fruits, not from cooked foods. Cooking can help make foods safer, helping to destroy foodborne organisms as well as some natural toxicants.
There is absolutely nothing wrong with eating raw foods. It can be an exciting way to eat, but it is not something that should be embraced blindly. It takes information and effort to do it correctly, as the body still requires a full complement of nutrients.
DEAR DR. BLONZ: I am in my 30s, with two children, and I have been taking multivitamins for most of my adult life. My mother has just been diagnosed with osteoporosis, and I want to add 1,200 milligrams of calcium to build my bones before I start to lose them. Is there a best time of day to take calcium and multivitamins? At present, I take mine after breakfast so I can flush out the excess vitamins with water throughout the day. -- T.M., Eureka, California
DEAR T.M.: There is definite wisdom to building bones during the first decades of life while the door is open. If you are going to take a calcium supplement based on calcium carbonate (the most common type), it is best to take it with or after a meal. Don't take more than 500 milligrams at a time, as this is about as much as your body can handle at once. Also consider calcium-rich foods, such as yogurt, or calcium-fortified beverages, such as orange juice.
Your multivitamin should include vitamin D, an important nutrient for bone health. Experts are now recommending up to 1,000 IU daily for adults. An active lifestyle, with weight-bearing exercise, plays a big role in building bones. It tells your body that your bones are needed, and the body responds by keeping them strong. There is a more detailed discussion of calcium at tinyurl.com/866w4sa.
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