Nutrition Hotline
By Reed Mangels, PhD, RD
QUESTION: Should vegetarians be concerned about mad cow disease?
RA, Florida
ANSWER: Mad cow disease, also called bovine spongiform encephalopathy (BSE), is a disease that affects the central nervous system of cattle and is ultimately fatal. Apparently, mad cow disease is caused by feeding cattle meat-and-bone meal composed of the bodies of cattle already affected with mad cow disease, or sheep with a similar disease called scrapie. A disease in humans called variant Creutz-feldt-Jakob disease is apparently caused by eating meat from cows with BSE. This untreatable disease affects the central nervous system leading to dementia and ultimately death. There is a long incubation period for this disease after eating contaminated meat. Although there is one report of variant Creutzfeldt-Jakob disease in a person who had been a strict vegetarian for several years prior to diagnosis, the source of the infection was apparently contaminated meat eaten before becoming vegetarian. Chances are very slim that any individual will get variant Creutzfeldt-Jakob disease. However, since, at this point, it appears that variant Creutzfeldt-Jakob disease is due to consumption of beef products contaminated by central nervous system tissue, becoming vegetarian will reduce risk of developing variant Creutzfeldt-Jakob disease.
Vegetarians can also reduce risk by avoiding supplements that contain tissue from cow brains, glands, and spinal cords. About 200 supplements (0.5% of the US market) contain cow tissue.
For more information on mad cow disease see
https://www.fda.gov/default.htmand search Mad Cow Disease
QUESTION: I am very concerned about my calcium intake. . . . Since I'm lactose intolerant, will I also lose the calcium in the dairy foods I try to eat? I mean if the milk does not digest, will the calcium fail to be absorbed? If I put dressing on leafy greens or cook them, is the calcium destroyed?
DM, California
ANSWER: You will still absorb some calcium even if the milk is not well digested. A key concern, however, is that in an attempt to avoid symptoms, you are limiting your use of dairy products and therefore not getting enough calcium.
Fortunately, dairy products are only one source of calcium. Why not try a fortified soymilk in place of cow's milk? Many brands of soymilk are fortified with calcium (check the label) and can easily replace cow's milk on cereal, in cooking, and as a beverage. There are also soy yogurts and soy cheese (many brands contain casein — a cow's milk protein that vegans will avoid — but do not contain lactose). There are even soy- and rice-based frozen desserts that you can enjoy without the gas, cramps, and diarrhea that often occur with lactose intolerance. Other good nondairy sources of calcium are tofu prepared with calcium sulfate (check the label), dark green, leafy vegetables like collard greens and kale, and calcium-fortified orange juice.
Calcium is a mineral and therefore pretty sturdy. Neither cooking nor adding dressing will reduce the calcium content of a food.
