Most low-carb Paleo meals involve a plate at least half-full of vegetables, which tends cut down on the concern about nutrient deficiency. But is there still a risk of being deficient in anything? None of the studies reported any subjects developing a nutrient deficiency on a low-carb diet. However, the review found that subjects on low-carb diets generally did eat less of several different nutrients: thiamin, folate, magnesium, calcium, iron, and iodine. But you can also get plenty of thiamin from meat and animal foods. For example, 1 pork chop has nearly three times as much thiamine as a cup of brown rice about 1 mg vs. Some people likely eat less folate when they switch to low-carb or Paleo because beans and peanuts are two big folate sources that suddenly get axed.
When excluding particular foods, food categories, or macronutrient groups from the diet, the opportunity for deficiency to present itself increases. Therefore, it is no surprise that pushback is due to lack of micronutrients in the keto diet. We are here to bust some of the myths surfacing around this topic. A close examination of our foods and their contents strongly supports the consumption of animal products. In fact, removing animal products from the diet poses more of a risk to the development of nutrient deficiencies than removing carbohydrate-rich products. This is particularly true when looking beyond the nutrient content of the food to how the nutrients are absorbed and metabolized. In general, meat and other animal products do not limit or may promote nutrient absorption, while plants can often contain antinutrients like phytates, oxalates, or glucosinolates which reduce nutrient absorption, nullifying any benefits associated with their contents.
Eating a balanced diet full of whole foods should provide adequate amounts of most micronutrients. However, in the context of a ketogenic diet, many high carbohydrate foods like fruits, vegetables, and grains contain many of the 28 known essential micronutrients. Over the years, there has been an increasing interest in micronutrients for their role in the prevention and treatment of disease. This interest is partially due to the increased understanding of the biochemical function of micronutrients, and interest in understanding micronutrient deficiencies associated with specific dietary interventions. However, a number of studies have found that the ketogenic diet provides sub-optimal levels of many micronutrients determined by DRI standards. In other words, the potential for micronutrient deficiency on a ketogenic diet is significant. That said, micronutrient deficiency on a ketogenic diet is not unexpected. Following a ketogenic diet, the balance of some micronutrients can become disturbed due to an increase in their excretion, and lowered consumption of micronutrient-rich foods such as fruits, vegetables, grains, and legumes. And, as the intracellular concentration of micronutrients falls, metabolic pathways and particular tissues will soon begin to be affected. The serious adverse effects associated with prolonged use of the ketogenic diet may be due to its reduced micronutrient content.