Government guidelines and advice from medical doctors can often lead people to believe that cereal grains are the foundation of a healthy diet. The food pyramid, now renamed the food plate, dictates that people should eat several servings of whole grains each day to provide an adequate supply of vitamins, minerals and fiber. This advice is given despite the fact that humans are poorly adapted to the consumption of cereal grains and that the scientific literature shows that grain consumption is linked to several health problems.
Grains have only been a part of the human diet for about 10,000 years, which is a very small time in the context of evolution. Just because humans can tolerate grains to a certain degree doesn’t mean that we are designed to consume grains or that we can achieve optimal health on a grain-based diet.
1) High-carbohydrate density and increased insulin load
Carbohydrates are eventually converted into a simple form of sugar, glucose, after they are consumed. Insulin is secreted and allows glucose to be transported into various cells throughout the body. Individuals who aren’t very physically active don’t have the need to continually refill their muscle and liver cells with glycogen, and these cells often start to become insulin-resistant on a grain-based diet.
Grains are the reproductive material of the plant, and plants don’t make the reproductive material to give away for free to animals. Cereal grains have evolved Lectins, Phytic Acid, Protease Inhibitors and other anti-nutrients that potentially disrupt normal gut physiology when they are consumed over time. Only certain anti-nutrients are problematic in humans, and they seem to operate in a dose-dependent manner.
Regular consumption of anti-nutrients in grains may lead to poor mineral absorption, autoimmune disease, leaky gut and low-level chronic inflammation. More studies on human subjects are needed to fully understand the detrimental effects of Lectins and other anti-nutrients on human health.
Studies and anecdotal reports indicate that gluten intolerance is much more common than previously thought, and many asymptomatic individuals react to gluten with some type of inflammatory response.
4) Insoluble fiber
While fruits and vegetables contain heart-healthy, soluble fiber that promote good gut flora, cereal grains are high in insoluble fiber that shouldn’t be eaten in excess. More insoluble fiber is often recommended for healthy digestion, despite the fact that healthy gut bacteria is the key to relieve constipation and achieve healthy bowel movements.
5) Dietary imbalances
Cereal grains have several dietary shortcomings, and a grain-based diet can disrupt adequate nutritional balance. Cereal grains are poor sources of fiber, minerals, vitamins and protein compared to animal products, fruits and vegetables. They contain no vitamin A, vitamin C, vitamin B12, calcium nor sodium, and several animal studies show that grain consumption can induce vitamin D deficiencies and alter the metabolism of several minerals.
Cereal grains only supply some of the essential amino acids, very few essential fatty acids and are also characterized by a high omega-6 to omega-3 ratio.
Traditional grain preparation
Some traditional cultures have been known to consume grains on a regular basis and still maintain excellent health. However, these populations have usually used soaking, sprouting and fermentation to make the grains easier to digest. These preparation methods remove or deactivate some of the anti-nutrients commonly found in grains, and fermentation is especially effective when trying to make grains more digestible.
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