Vegetarian nutrition is the set of health-related challenges and advantages of vegetarian diets. Appropriately planned vegetarian diets are healthful and nutritionally adequate for all stages of the human life cycle, including during pregnancy, lactation, infancy, childhood, and adolescence. However, vegetarian diets deficient in vitamin B12 or calories may compromise children's health and development. The UK National Health Service recommends that vegetarian diets should also follow the general recommendations for healthy diets, such as low fat, salt and sugar intakes and 5 fruits or vegetables a day. Qatar's public health ministry states, "One cannot be a healthy vegetarian by going to a fast food restaurant and ordering french fries and soda!". Vegetarian diets tend to be rich in carbohydrates, omega-6 fatty acids, dietary fibre, carotenoids, folic acid, vitamin C, vitamin E, potassium and magnesium. They are possibly low in saturated fat, cholesterol, and animal protein. Critical nutrients Protein Despite the long-standing, widespread belief that vegetarians must consume grains and beans within a short time to make a complete protein that contains all 9 essential amino acids that must be supplied through diet, this has never been substantiated by research. The protein-combining theory was brought to popular attention after being promoted in Frances Moore Lappé's 1971 bestselling book Diet for a Small Planet. In later editions of the book, starting in 1981, Lappé withdrew her contention that protein combining is necessary. Plant foods rich in protein include soy beans and soy products such as tofu, veggie burgers, and soy milk; other legumes; nuts and seeds; and cereal grains. Vitamin B12 Vitamin B12 deficiency can be extremely serious and lead to megaloblastic anemia, nerve degeneration and irreversible neurological damage. Vegetarians may get vitamin B12 from eggs and dairy products (milk, cheese, etc.); for some, this is adequate, while others may still remain B12-deficient. More broadly, according to the Academy of Nutrition and Dietetics, even the form of vitamin B12 sourced from animal products is protein-bound and not as easily digested as supplements, especially as people age, and therefore B12 supplementation is recommended for everyone over the age of 50. Pregnant and lactating vegetarian mothersand breastfed infants if the vegetarian mother's diet is not supplementedshould also use supplements, whether B12-pills, B12-injections, or B12-fortified foods, if they don't get adequate vitamin B12 from animal products like eggs or dairy. Generally, humans need 2.4 to 3 micrograms of vitamin B12 each day. There are cases to