Legumes: Paleo Vs Keto — What's The Difference?

The Paleo diet is based on the idea that many of today's health problems are caused by foods that are new to the human diet. As such, the diet focuses on eating foods that our caveman ancestors ate, including hunted, fished, gathered, or plucked foods, with no grains or beans. Legumes are also avoided on the Paleo diet due to the presence of lectins, which are thought to damage the gut lining and increase inflammation.

On the other hand, the Keto diet is a low-carb, high-fat diet, which focuses on maintaining a state of ketosis through very low carbohydrate intake. While legumes are generally considered high in carbs and not suitable for strict Keto, some low-carb legumes, such as black soybeans and peanuts, can be included in small portions.

Therefore, while both diets have restrictions on legumes, the reasons behind these restrictions differ. Paleo avoids legumes due to the ancestral diet and the presence of lectins, while Keto restricts legumes due to their high carb content.

Legumes are not part of our ancestral diet

The paleo diet is based on the principle that eating foods available to early humans will promote optimal health. It is thought that people in the Paleolithic era did not have farms that provided food groups like grains and most dairy, and of course, no modern-day processed foods. The paleo diet eliminates grains, legumes, processed sugar, and most sources of dairy.

Legumes are widely considered to be sustainable and healthy sources of protein, fiber, minerals, B-vitamins, folic acid, and other nutrients. They are unique in the plant kingdom in that they produce protein largely by taking nitrogen (and carbon dioxide) from the air. This provides a sustainable alternative to using nitrogen fertilizer, thus reducing the burden on our soil, waterways, and atmosphere.

However, legumes are not part of the paleo diet because they are not considered to be part of our ancestral diet and because they contain toxic anti-nutrients like lectin and phytic acid.

The first argument is not supported by evidence. Recent analysis of Neanderthal tooth plaque revealed that they consumed wild varieties of peas and fava beans. Since early humans are thought to have eaten a more diverse diet than Neanderthals, it is safe to assume that our human ancestors also ate legumes. Dr. Stephan Guyenet also points to several contemporary hunter-gatherer groups that consumed significant amounts of legumes, including the !Kung San of the Kalahari desert and the Australian Aborigines.

The second argument is also not supported by evidence. Cooking legumes for as little as 15 minutes or pressure-cooking them for 7.5 minutes almost completely inactivates the lectins they contain, leaving no residual lectin activity in properly cooked legumes. Lectins are also present in at least 53 fruits, vegetables, spices, and other commonly eaten plants, including carrots, zucchini, melon, grapes, and cherries.

Phytic acid is the storage form of phosphorus found in many plants, especially in the bran or hull of grains and in nuts and seeds. While diets high in phytic acid contribute to mineral deficiencies, humans can tolerate moderate amounts of it without harm. There is even evidence that phytic acid may have some beneficial effects, such as preventing the formation of free radicals, preventing the accumulation of heavy metals in the body, and playing a role in cellular communication.

In conclusion, legumes are not part of our ancestral diet, but this argument is not supported by evidence. Additionally, the claim that legumes contain toxic anti-nutrients is also not supported by evidence, as properly cooked legumes do not contain harmful levels of lectins and phytic acid.

Legumes contain phytic acid, which prevents the absorption of minerals from food

Legumes contain phytic acid, which is a natural compound found in plant seeds. Phytic acid is often referred to as an "anti-nutrient" because it can block the absorption of some minerals in the gut during digestion. Specifically, phytic acid prevents the absorption of iron, zinc, and calcium. This means that when legumes are consumed, the phytic acid binds to these minerals, creating phytates that cannot be absorbed by the body.

However, the effects of phytic acid are not generally worrisome for those who eat well-balanced diets, as the body can adapt to a diet high in phytic acid. In addition, there are several preparation methods that can significantly reduce the phytic acid content of legumes, such as soaking, sprouting, and fermentation. For example, cooking legumes for one hour can reduce their phytic acid content by up to 80%.

Furthermore, phytic acid also has several health benefits. It serves as an antioxidant and may protect against insulin resistance and colon cancer. Overall, while legumes do contain phytic acid, which can prevent the absorption of certain minerals, the impact of phytic acid can be mitigated through proper preparation and a well-balanced diet.

Legumes contain lectins, which can impair growth and damage the intestine

Legumes contain lectins, which are a family of proteins found in almost all foods, especially legumes and grains. Lectins can impair growth and damage the intestine in a few ways:

• Impaired nutrient absorption: Studies on animals suggest that high doses of isolated lectins or raw legume flours lead to a reduction in the absorption of certain nutrients. However, this isn't very applicable to humans, as we generally don't eat raw legumes, and our diets have very low levels of lectins in comparison.
• Increased intestinal permeability (aka "leaky gut"): Limited research in animals links lectins to increased intestinal permeability. These studies use isolated lectins or raw legumes, which are not typical human foods.
• Altered gut bacteria: Animal studies using purified kidney bean lectin have resulted in bacterial overgrowth and poisoning. However, properly cooked kidney beans are safe to eat.
• Immune system stimulation: There are theories that lectins may trigger autoimmune diseases or inflammatory diseases, but no human studies have been conducted.

Proponents of the paleo diet claim that lectins are harmful and that people should remove legumes and grains from their diet. However, lectins can be virtually eliminated through cooking. Boiling legumes in water eliminates almost all lectin activity, and the benefits of the healthy nutrients in these foods far outweigh the negative effects of trace amounts of lectins.

Legumes are not nutrient-dense

The paleo diet is based on the principle of eating foods that were available to early humans, while the keto diet focuses on decreasing carb intake. Paleo eliminates grains, legumes, processed sugar, and most sources of dairy, while keto restricts all rich sources of carbohydrates, including starchy vegetables, most fruits, grains, sweeteners, and most legumes.

Legumes are not allowed on paleo due to their high content of lectins and phytic acid. However, this is controversial within the scientific community, as legumes are also a good source of fiber, vitamins, and minerals.

Legumes are a family of plants that include beans, lentils, peanuts, and peas. They are a common ingredient used in various cuisines worldwide and are known for their versatility and delicious taste. While legumes are a good source of several important nutrients, they are not considered nutrient-dense. Nutrient-dense foods are those that provide a good amount of vitamins, minerals, and other essential nutrients with relatively few calories.

Legumes are high in folate, manganese, iron, and magnesium, as well as plant-based protein and fiber, both of which are essential for several aspects of health. Protein is crucial for immune function, body composition, tissue repair, and healthy growth and development. Fiber has been shown to reduce blood pressure, lower cholesterol levels, improve insulin sensitivity, and enhance weight loss.

However, when compared to other nutrient-dense foods such as fruits, vegetables, lean proteins, whole grains, nuts, and seeds, legumes fall short in terms of nutrient density. For example, beans and lentils, which are staples of plant-based diets, are high in protein and fiber but lack the complex carbohydrates, vitamins, and minerals found in whole grains.

Additionally, the paleo diet emphasizes the importance of unprocessed, natural foods, and legumes are often processed and canned, which can further reduce their nutrient content. While legumes can be a healthy addition to one's diet, they should not be relied upon as a primary source of nutrients due to their relatively low nutrient density compared to other whole foods.

Legumes contain FODMAPs, which can cause digestive issues

Legumes are a rich source of prebiotic fibres, which provide fuel for the healthy bacteria in the gut. However, the galacto-oligosaccharide (GOS) found in legumes is one of the FODMAPs that people, even without IBS, don't tolerate well. Legumes and pulses that are particularly high in GOS include red kidney beans, split peas, falafels and baked beans.

The paleo diet eliminates legumes, along with grains and most sources of dairy. The keto diet also eliminates grains and most legumes, but because of their carbohydrate content. Legumes are not allowed on paleo because of their high content of lectins and phytic acid. However, legumes are a good source of fibre, and research supports eating legumes as part of a healthy diet.

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