A Hidden Danger with Nuts, Grains, Beans and SeedsFebruary 19th, 2009
Whole grains, beans, nuts, and seeds are widely recognized as healthy foods, but without taking a few important precautions, they may not be nearly as healthy as you think.
Most people buy grain products that are heavily processed and nuts that are roasted and salted. The processing involved reduces the nutritional quality of the food and usually involves the addition of unhealthy additives. If it’s not enough that people eat these processed varieties on a regular basis, the problem is made worse by some of the undesirable substances that exist in grains, beans, nuts, and seeds when they’re not prepared properly. As such, it’s best to buy these foods in their natural and whole form, or as close to it as possible, and prepare them yourself. If that’s not possible, you should at least buy from companies that have already done the work for you.
It’s always best to eat natural whole foods and this certainly applies to nuts, grains, beans, and seeds. Unfortunately, it’s difficult to find these foods in their raw form at a typical grocery store, and even if you do, it’s unlikely that they’re organic which means that they’re more likely to contain chemical residues and be less nutritious. The best place to find a large selection of raw organic nuts, grains, beans, and seeds is a local health food store. Once you find a place to buy high quality varieties of these foods, you’ll have the ability to properly prepare them and make them into the truly healthy foods that they’re often claimed to be.
The following are a few problems that are inherent with these foods and some suggestions on how to resolve them.
Phytic Acid and Reduced Mineral Absorption
Phytic acid is a substance found in cereal grains, nuts, seeds, and legumes that prevents premature germination and stores nutrients for plant growth.1,2,3,43,44 Research has shown that it also reduces the absorption of the important minerals calcium, magnesium, iron, and zinc when consumed by humans.4,5,6,7,43,45,46 Phytic acid also has potential to reduce the digestibility of protein.17 This doesn’t only apply to the minerals and protein in the food containing the phytic acid, but also the food that you eat with it.
Frequent consumption of foods that contain phytic acid can lead to nutrient deficiencies and can cause a wide variety of issues including skin problems, impaired appetite, mental fatigue, altered gene expression, and impaired immunity due to zinc deficiency,8,9 anemia and poor development in infants and children due to iron deficiency,12 and increased risk of rickets and bone softening due to calcium deficiency.10,11. Although it’s rare for these problems to occur in developed countries as a result of nutrient deficiencies, even a mild deficiency is enough to detract from optimal health and cause undesirable symptoms. For example, a mild zinc deficiency, which can result after just a few months of consuming just 1 milligram per day less than needed, can reduce testosterone production and alter immune function.9
Enzyme Inhibitors and Impaired Digestion
Many plant foods contain protease inhibitors, also known as trypsin inhibitors, which block enzyme function and protect plants from insects.13 These inhibitors can also prevent protease enzymes from digesting protein in the human digestive tract which can burden the pancreas with the need to produce more enzymes. Based on animal research, it’s believed this burden can potentially lead to hypertrophy and cancer of the pancreas in humans.14,15 According to the work of Dr. Edward Howell, this increased requirement for digestive enzyme production can also deplete the body of valuable resources needed for other physiological functions.16
The Benefits of Soaking
Cereal grains, beans, nuts, and seeds are all considered plant seeds, and when a plant seed undergoes germination, a lot of changes occur that provide the growing plant with needed nutrients. This includes the breakdown of phytic acid and complex carbohydrates, the inactivation of protease inhibitors, and the increased availability of vitamins and minerals, all of which increase the nutritional value of the seed and improve its digestibility.
In nature, germination typically occurs when a plant seed encounters conditions that are favorable for its growth which typically involves water. As such, the germination of grains, nuts, beans, or seeds can be easily initiated by soaking them in water. Although mostly focused on grains and beans, research has shown soaking to be quite effective for the reduction of phytic acid in as little as 12 hours as well as the subsequent increase in mineral availability18,19,20,21,22,23,24,25,47 and for the reduction of protease inhibitors starting at about 36 hours19,22,28,29. In both cases, the amount of reduction increases with time, especially for protease inhibitors. Soaking can also increase the content of some components of the vitamin A, B, C, and E complexes,37,38,39 and through the activation of amylase enzymes, helps to break down complex carbohydrates and improve their digestibility.40,41 This latter benefit is especially important for optimal digestive health because it will reduce the possibility of complex carbohydrates from being fermented in the intestines and contributing to the proliferation of undesirable bacteria.
When time is limited, the combination of soaking and cooking has been shown to be much more effective than only soaking for a short duration.30,25 However, because cooking has also been shown to be less effective at reducing phytic acid,32 soaking is still important. For grains and beans, light cooking is generally a good idea anyway since it further improves digestibility and deactivates natural plant toxins that may still exist after soaking.
The seeds being soaked can easily absorb chemicals from the water or container that they’re soaking in, and in some cases, such chemicals may be even more of a concern than the phytic acid and protease inhibitors that you’re going out of your way to avoid. As such, it’s important to use a glass container and filtered water. Because phytase enzymes tend to function optimally at a slightly acidic pH at warmer temperatures,35,36 it may also be beneficial to use warm water and increase its acidity with something like lemon juice. It’s also believed that adding sea salt will help to neutralize the enzyme inhibitors.42
The Benefits of Fermentation and Fermented Foods
Similar to soaking, fermentation is another method of reducing phytic acid and protease inhibitors that has been shown to be even more effective in some cases.18,34,23,45 This is because the lactic acid bacteria typically used for fermentation naturally produce the phytase enzymes that break down phytic acid.48 However, this generally applies to grains and beans more so than nuts and seeds and is a slightly more involved process that usually involves the use of a starter bacteria culture.
The consumption of fermented food has been shown to improve the intestinal balance of beneficial lactic acid bacteria.49 Based on this and the phytase producing capability of the bacteria, the consumption of fermented foods may be another effective way to reduce the potential of dietary phytic acid impairing mineral absorption.50
Products that are Already Soaked
Although soaking grains, beans, nuts, and seeds is very easy, some people might consider it too much of a hassle. Furthermore, products such as bread, nut butters, or snack bars cannot be soaked unless you make them yourself. Fortunately, there are some food manufacturers that go through the trouble for you.
For grain based products, Food for Life is a highly regarded company that soaks the grains that go into many of their products. They have a wide range of products ranging from cereals, pastas, breads, and tortillas.
For nuts, Better Than Roasted is an excellent line of raw organic nuts and seeds that are soaked prior to sale. They also have a great line of nut and seed butters that are made from the same nuts. The almond butter is excellent!
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