Grains have gotten a bad rap in recent years, with the rise in popularity of paleo and ketogenic diets turning people away from many carbohydrate foods. But oats have unique health benefits that should be taken into account.
The story of oats is a classic rags-to-riches tale, if ever that could be applied to food. Once considered acceptable food only for livestock, oats are now regarded as one of the healthiest foods on the planet. Valued by the weight-conscious as a filling, low-calorie meal option, and approved by low-carb dieters thanks to a slow-burning, low-glycemic profile. Still a staple food in many countries, oats have finally gone mainstream. And this is a dietary trend with lots of merit.
Oats are a high-energy, low-fat source of complex carbohydrates, providing hours of steady energy without blood sugar spikes or crashes. Oats are low-calorie, easy to prepare, and very versatile, accommodating an array of toppings such as fruits, nuts, seeds, and honey or maple syrup. Oats and groats (the whole-grain kernel without the husk) are always 100 percent whole grain, with germ, endosperm, and nutrient-rich bran intact. Regardless of the variety you choose—rolled, steel-cut, pin oats, old-fashioned, or instant—the high soluble fiber content of oats keeps your energy steady and provides a satisfying sense of fullness. Oats are a great source of important vitamins and minerals, including calcium, zinc, iron, manganese, thiamine, B-vitamins, vitamin E, and folic acid, essential for healthy fetal development. And if those aren’t enough reasons to make oats your new go-to breakfast, here are more powerful health benefits of eating oats that you should know about!
Improves Blood Lipid Profiles (‘Cholesterol’)
While we do not believe that present-day guidelines for lowering cholesterol address the root causes of heart disease, finding natural alternatives to statins drugs, whose toxicity is profoundly underreported, can have life-saving consequences. Therefore, food-based approaches are needed more than ever. Oats have been accepted worldwide by food standards agencies as having a cholesterol-lowering effect when regularly included in the diet. Due in part to this increased awareness, in 2014, a group of international researchers sought to update previous meta-analysis with new findings on oats’ actions on improving blood lipid profiles. Much of this research focused on an isolate in oats called oat beta-glucan, water-soluble polysaccharides derived from the endosperm of oat kernels, known for their cholesterol- and blood sugar-lowering properties. After a review of 28 randomized controlled trials, researchers concluded that subjects who consumed a minimum of 3 grams per day of oat beta-glucan experienced reduced low-density lipoprotein (LDL) and total cholesterol, relative to control subjects. Subjects with the highest pre-trial LDL cholesterol experienced the greatest reductions, indicating a normalizing effect. More studies echo these findings.
Other grains do not have the same effect on blood lipid profiles that has been observed in oats. In 2002, wheat cereal, popularized as an oatmeal equivalent, was tested against oatmeal for cholesterol effects in middle-aged and older men. In this study, 36 overweight men aged 50-75 years, were randomly assigned to consume either wheat or oat cereal for 12 weeks. Both cereals provided the same amount (14 grams) of dietary fiber. Baseline levels of blood lipids were measured, and whole-body insulin sensitivity was frequently sampled via intravenous-glucose-tolerance tests. Researchers concluded that compared with wheat cereal, oats produced lower concentrations of LDL cholesterol without producing adverse changes in blood triacylglycerol or HDL-cholesterol concentrations. There was no impact on blood glucose, prompting researchers to declare that oats may potentially be cardioprotective and safe for individuals with blood sugar sensitivities, two hypotheses that are significantly supported by the following clinical research.
Good for Heart Health
Plant polyphenols are micronutrients in plant-based foods that are responsible for imparting many health benefits when consumed, including bolstering resistance to a host of degenerative diseases such as cancer and cardiovascular diseases. The amount of benefit we get is largely dependent on quantity and quality of polyphenols consumed. A 2006 study on oat polyphenols confirmed previous scientific findings that oats may offer additional heart benefits beyond simply lowering cholesterol. In this study, a polyphenol which is unique to oats called avenanthramide-c, was shown to inhibit the proliferation of vascular smooth muscle cells, an important factor in the initiation and progression of atherosclerosis.
Additional heart-healthy benefits were observed in this study on the effects of oat bran on blood lipid profiles in patients with an increased risk of coronary heart disease. In the study, 235 overweight males with high cholesterol were organized into three groups: a control and two test groups. Both test groups were placed on a modified low-fat diet, one of which was also provided 35-50 grams of oat bran supplementation each day. The most significant decreases in total cholesterol, low-density lipoprotein cholesterol, and apolipoprotein B were found in the group receiving oat bran-enriched food. Oats’ benefits to the heart have even been witnessed in the brain. A study published in 2013 examined twenty-seven healthy subjects aged 60 and older who were given supplementation of wild green oat extract for six months. Compared with placebo, wild green oat extract supplementation was shown to relax smooth muscle cells within the vessel walls of systemic and cerebral arteries, confirming results of a similar study from 2006 that used oat polyphenols instead of wild oat extract.
Maintaining healthy blood pressure is another facet of good heart health. A 2010 study sought to assess the effects of consuming whole-grain foods on markers of cardiovascular disease risk in high-risk individuals. Researchers selected middle-aged, otherwise healthy individuals, and created one control group, and two test groups. One test group was fed a modified diet containing wheat grains only, while the other test group was fed the modified diet plus wheat and oat grains, diets they followed for twelve weeks. According to the study, “The primary outcome was a reduction of cardiovascular disease risk factors…which included [reduced] lipid and inflammatory marker concentrations, insulin sensitivity, and blood pressure.” Both systolic and pulse pressure were significantly reduced in the whole grains groups, the most impactful outcome for heart health seen in this trial. These findings and others like them suggest that whole grains, especially those derived from oats, can play a role in the maintenance of good heart health.
Stabilizes Blood Sugar
It’s a common belief that individuals with blood sugar sensitivities should not consume grains, breads, and cereal products. This is generally a good rule to follow, as most commercially-prepared breads and cereals contain simple sugars and denatured (non-whole) grains which have the effect of sending insulin spiking and blood sugar crashing soon after a meal. This is especially true for individuals with Type 2 diabetes, who require low-glycemic grain products to control blood sugar and decrease the odds of progression to insulin-dependency. A 2005 study compared post-meal glycemic response of two oat bran flour products in patients with Type 2 diabetes. Researchers found that both of the oat flour products decreased glucose excursion from baseline, and oats’ high-beta glucan was an active ingredient in decreasing post-meal glycemic response in subjects.
An earlier study on the power of oat bran sought to determine the long-term effects of oat bran bread products in the diets of subjects with non-insulin-dependent diabetes. Bread and other grain-based carbohydrates can be trigger foods for people with blood sugar sensitivities, however, researchers concluded that consuming oat bran-derived bread products actually improved glycemic, insulinemic, and lipidemic responses in test subjects. Such positive study outcomes tend to inspire further research, as scientists’ quest for the holy grail of health steadily continues. In 2015, researchers conducted a large-scale review of the metabolic effect of oats on Type 2 diabetes patients, in an attempt to better understand the mechanisms at work in this exceptional grain. The review included results from fourteen controlled trials and two uncontrolled observational studies published in PubMed database up to August 23, 2015. As compared with control groups, consuming oats significantly reduced concentrations of average plasma glucose concentration, fasting blood glucose, total cholesterol, and low-density lipoprotein cholesterol. Oatmeal also significantly reduced acute post-meal glucose and insulin responses compared with the control meal. The study confirmed the beneficial effect of oats intake on glucose control and lipid profiles in Type 2 diabetic patients, paving the way for potential uses for oats in the treatment of Type 1, insulin-dependent diabetes.
Heals the Gut
According to celiac.org, celiac disease is a serious, hereditary autoimmune disorder in which the ingestion of gluten leads to damage in the small intestine. An estimated 1 in 100 people are affected worldwide, including 2.5 million Americans who are currently undiagnosed and at risk for long-term health complications. Oats are one of the few gluten-free grains, as long as they are uncontaminated (oats are often processed in plants that also process wheat, barley, and other gluten-containing grains). Beyond their gluten-free status, oats have been observed to have healing effects in individuals with celiac disease. In 2010, a group of researchers, inspired by previous studies showing that consumption of oats improves intake of vitamins and minerals in celiac patients, conducted a study whose aim was to clarify the effect of consuming large quantities of oats on nutrient intakes in celiac patients in remission. The goal for subjects was to consume 100 grams of oats per day. Results showed that intake of vitamin B1, magnesium, and zinc increased significantly during the period of dietary modification.
In addition to increasing nutrient absorption, celiac patients who include oats in their diet may receive further benefits. It is well-known that a gluten-free diet omitting other grains is the only effective treatment for celiac disease. However, according to researchers, “the necessity of excluding oats from the diet has remained controversial.” A study on children with celiac disease found that oats do not trigger systemic auto-antibodies, nor mucosal auto-antibodies in the intestines. Another study on children with newly-diagnosed celiac disease found that despite being previously off-limits to celiac patients, oats appear safe and non-toxic, regardless of age or length of time since diagnosis.
The controversy surrounding oats and celiac has to do with proteins called avenins, similar to gliadin from wheat, which can trigger celiac disease in a small proportion of people, as well as the aforementioned contamination problem. A 2005 study sought to determine if different varieties of oats may exert differing toxicities in celiac patients. In this study, three types of oats were tested: an Italian oat variety called Astra, and two Australian varieties, Mortlook and Lampton. Avenins from Astra and Mortlook showed much higher levels of intestinal activity than the Lampton variety of oats, causing proteins to agglutinate and disrupting lysosomes. Despite being widely tolerated among individuals with celiac disease, this study indicates that caution should still be exercised at the individual level. According to researchers, “It is important to realize that constant, small amounts of active proteins in the diet, such as certain avenins, may prevent complete recovery of the intestinal mucosa in this disease.” It is therefore important for individuals with celiac disease to assess their own level of reactivity to oats in the diet.
Part of the intestinal health benefits of oats lies in their ability to reduce gut permeability, a factor in other intestinal disorders such as leaky gut syndrome and certain allergies. A 2016 study investigated the influence of the dietary fiber oat beta-glucan on nutrient composition and the permeability of intestinal mucus. Pigs were fed a standard diet or a diet containing oat beta-glucan for 3 days, after which samples of tissue and intestinal mucus were collected. Samples indicated that 90% of the oat beta-glucan was released in the small intestine which demonstrated a reduction in permeability through reduced transfer of bile and lipids through the intestinal mucus layer, and a reabsorption of bile by soluble fiber. Researchers concluded definitively that “Increasing dietary oat fiber decreases the permeability of intestinal mucus.” This research is confirmed by studies demonstrating that oats can repair alcohol-induced gut leakiness in animal studies. There is even reason to suspect that tricin, a flavonoid found in oats, can suppress formation of inflammation-associated colon cancer cells, giving rise to the potential use of tricin for clinical trials of colorectal cancer chemoprevention.
 Biesiekierski JR (2017).”What is gluten?”.J Gastroenterol Hepatol (Review). 32 Suppl 1: 78–81. doi:10.1111/jgh.13703. PMID 28244676.