Health Benefits of Grains and Pseudograins
Grains are the fruits or seeds of grasses (family Poaceae or Gramineae) whereas pseudograins (amaranth, buckwheat, quinoa and chia) are the starchy seeds of broad-leafed plants. In their whole form, grains and pseudograins are a nutritionally valuable concentrated source of fiber, which is responsible for most of their health benefits. For example, a 2017 meta-analysis showed that, for every 30 grams of whole grains we eat daily, risk of all-cause mortality decreases by 8%. In contrast, refined grains do not improve health outcomes.
Research has shown oatmeal can be protective against a variety of health conditions. Over 50 human studies (the first one conducted in 1963!) have demonstrated that oats have cholesterol-lowering properties, reducing both total and LDL cholesterol by up to 23% (while preserving or sometimes increasing HDL cholesterol) when consumed at levels of 35 to 120 grams per day. And, in over a dozen studies, oat consumption has been shown to improve levels of both fasting and post-meal blood sugar and insulin. In fact, meals containing between 6 and 8.4 grams of fiber from oats can reduce the blood sugar response by up to 50%, with the suppressed response lasting up to eight hours. A review of observational studies also found that high oat intake is associated with a 10% reduction in cancer risk!
Research has shown that rice can indeed contribute to good health! In a study of over 83,000 Japanese adults, steamed rice consumption was associated with reduced risk of cardiovascular disease mortality in men, even after adjusting for other lifestyle factors. Likewise, whole-grain rice (especially the bran) contains important polyphenols—including phenolic acid, anthocyanin, and proanthocyanidins—that have antioxidant activity and may reduce the risk of cancer and heart disease. Rice bran itself has also been shown to reduce LDL cholesterol levels (possibly due to its phytosterol content) and potentially protect against colorectal cancer.
One of the most exciting potentials of rice is its resistant starch content, which has significant prebiotic activity and can greatly benefit gut health. Although rice doesn’t contain some of the unique fibers that make certain grains particularly gut-friendly (such as the β-glucan in oats and barley), some cooking methods can increase the resistant starch content of rice. Cooking rice as normal, and then cooling it to room temperature or refrigerator temperature, can cause starch retrogradation and more than double rice’s resistant starch content. In one experiment, researchers analyzed the resistant starch content of freshly cooked white rice, cooked white rice that had been cooled for 10 hours at room temperature, and cooked white rice that had been cooled for 24 hours at 4°C and then reheated. Compared to 0.64 grams per 100 grams of freshly cooked rice, the room-temperature cooled rice contained 1.30 grams of resistant starch per 100 grams, and the 4°C-cooled rice contained 1.65 grams of resistant starch per 100 grams. Studies have shown that rice, especially brown rice, improves the composition of the gut microbiome.
While fresh corn is classified as a vegetable, maize or cornmeal is classified as a grain. Corn contains a range of compounds with known health-promoting effects, including phenolic acids (such as vanillic acid, coumaric acid, ferulic acid, caffeic acid, and syringic acid) and plant sterols. The phytosterols in corn are known to reduce LDL levels (without affecting HDL levels) by inhibiting cholesterol absorption in the intestine, and the lignans in corn have anticancer and antioxidant properties. Corn bran has been shown to enhance satiety when added to lower-fiber foods like muffins (even more so than oat bran and barley bran), and resistant starch from corn reduces glucose and insulin responses from meals. In a study of 47,228 adult men, consuming popcorn at least twice per week was associated with a 28% lower risk of diverticulitis (compared to consuming popcorn less than once per month) over the course of 18 years.
Examples of Grains and Pseudograins
- corn (aka maize)
- job’s tears
- wheat (all varieties, including einkorn, durum, semolina)
- wild rice
Nutrients in Grains and Pseudograins
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