Meat offers many important nutrients that keep the body functioning properly. Failure to plan your diet properly can lead to significant nutritional deficiencies (Phillips). Health risks include: calcium deficiency, low calories, decreased muscle tone, limited variety, and lack of fat (Meanley). Due to the majority of plants being protein deficient, vegans tend to combine their diet (e.g. tortillas and beans) to provide all the necessary amino acids (Cherepa). It may take a little creativity to find foods that pair well and provide the right nutrients; but it can be done. Vitamin B₁₂ and vitamin D are two important nutrients that vegans in particular don't get enough of. A lack of vitamin B₁₂ can pose a risk at any age due to its important role in maintaining normal functioning of the brain and nervous system, as well as in blood formation. The main function of vitamin D is to maintain normal blood levels of calcium and phosphorus. It also forms and maintains strong bones by helping the body absorb calcium. Lack of vitamin D would have a greater impact on older people, as they are at high risk of hip fracture. In old age, it is difficult for them to function and complete daily tasks, but a hip fracture will further limit their abilities and increase their dependence on others. Women following a vegetarian diet during pregnancy should be extremely careful due to birth defects. The Avon Longitudinal Study of Pregnancy and Childhood (ALSPAC) found that there is an increased risk of giving birth to a boy with hypospadias (a birth defect) if mothers followed a vegetarian diet during pregnancy ( Phillips). The key to a healthy meat-free diet is to always watch what you eat. It may be complicated, but it is necessary if you intend to become vegetarian.