American Medical Association Family Medical Guide - American Medical Association [37]
Vegetarian Diets
With improved understanding about the role of nutrition in health, vegetarian diets are more popular than ever and are very healthy, as long as they supply adequate amounts of protein, vitamin B12, calcium, vitamin D, iron, and other essential vitamins and minerals that are more abundant in animal-based foods. Vegetarians are less likely than meat eaters to develop heart disease, high blood pressure, and some cancers, or to be overweight. But vegetarians can risk developing iron deficiency anemia (see page 610) or being malnourished if they are not knowledgeable about appropriate food choices.
There are three types of vegetarian diets—ovolactovegetarian, lactovegetarian, and vegan. Ovolactovegetarians consume eggs and dairy products along with plant foods. Lactovegetarians eat dairy products but not eggs. Vegans eat only plant foods and, for this reason, are most at risk for vitamin and mineral deficiencies; however, a vegan diet can be very healthy when plant-based foods are combined. A vegetarian diet for children and pregnant women must be planned very carefully to ensure that they consume sufficient calories, calcium, protein, and essential nutrients to meet all their vitamin, mineral, and amino acid (protein) needs.
If you’re not ready to be a full-time vegetarian, at least try eating a few vegetarian meals every week. Occasionally having pasta with a meatless sauce, bean or avocado burritos, or mushroom barley soup for lunch or dinner along with salads and fruits will vary your menu, save money, and provide huge health benefits.
Nutritional Needs Change Throughout Life
To a large extent, your age determines your nutritional needs. Newborns and infants have special nutritional needs that are best met by breastfeeding (see page 539). Doctors recommend that mothers breastfeed their babies for the first 12 months of life. Breast milk supplies better nutrition than commercial formula, promotes healthy brain development, and provides infection-fighting antibodies from the mother. Also, infants should not be given cow’s milk until they are 1 year old because it can cause an allergic reaction and is too concentrated for an infant’s digestive system.
Food Sensitivities
A food sensitivity is a reaction to an additive or ingredient in a food, but the reaction is not related to the immune system. Sulfites, substances that occur naturally in the fermentation of wine and are used as preservatives on fresh fruits and vegetables, are common additives that cause food sensitivity. Sulfites can trigger severe asthmalike symptoms such as shortness of breath and chest tightness. In the United States, foods and wine that contain sulfites must indicate it on their label. Flavor enhancers (such as monosodium glutamate) and food coloring (mainly yellow dye No. 5) can cause adverse reactions such as headaches. Sometimes a naturally occurring substance called histamine can cause a reaction known as histamine toxicity, which mimics an allergic reaction. Cheese, some wines, and tuna and mackerel sometimes contain large amounts of histamine.
Different people can have different reactions to the same foods. If you think you could be having problems with a particular food, see your doctor; he or she can help you identify the foods that trigger a reaction so you can avoid them.
Toddlers and preschoolers sometimes become picky eaters as their newfound independence propels them into a multitude of activities that seem much more interesting than eating. Start to teach good nutrition habits at this age. Offer your child a variety of foods without forcing him or her to eat any particular food. When deciding how much food to give your child, use this convenient rule of thumb: about 1 tablespoon of each food per meal for every year of age. For example, a typical dinner for a 5-year-old might be 5 tablespoons of chicken along