Health Benefits Of Oats

What are oats?

Oats, also known by their scientific name, Avena sativa, are one of the oldest cultivated whole grains. A whole grain is any cereal grain that has retained the three main parts of the kernel: the endosperm, germ, and bran. Unlike more refined grains, whole grains are less processed, and as a result, have more nutritional value. You can buy oats in various forms that have been processed to different degrees. Oat groats are the least processed, followed by steel-cut oats, Scottish oats, rolled oats, quick oats, instant oats, oat bran, and finally oat flour. Often, the less processed the oats are, the longer they take to cook.

When you think of oats you probably think of porridge, overnight oats, granola, or even flapjacks. You can also find oats in oatcakes, oatmeal cookies, oat flour, and oat milk is becoming increasingly popular. While they may seem like a mundane staple to have in your pantry, they have been shown to have extensive health benefits. 

Keep reading this article to find out what these health benefits are, their nutritional value, and some potential side effects of consuming oats. You might not think they’re boring by the end!

Health benefits of oats

Digestive health

Oats are a high-fibre food, which means they contain high amounts of ‘non-digestible’ carbohydrates. Fibre can be further categorised as soluble or insoluble and is an important component of our diet because of the health benefits it has been shown to have.

Soluble fibre ‘dissolves’ in water and in your digestive tract, and it has a beneficial effect on the absorption of compounds and nutrients into the bloodstream. For example, it helps to prevent the ‘bad’ cholesterol associated with cardiovascular disease from being absorbed. In contrast, insoluble fibre does not ‘dissolve’ and instead helps to increase stool size and improve its composition.¹ This helps to prevent constipation and supports your digestive health.

Antioxidant activity

Oats contain several bioactive compounds that have been shown to have an antioxidant effect on the human body.² Antioxidants are any molecules or compounds that prevent oxidative stress created by reactive oxygen species (ROS) and free radicals in the body. This oxidative stress can damage cells and tissues, leading to chronic inflammation and even diseases such as cancer.³

The antioxidant compounds found in oats include: 

• Vitamin E³
• Phytic acid³
• Polyphenols and other Phenolic compounds³
• Sterols³
• Avenanthramides³
• Avenacosides³

A review paper examined several studies that showed the antioxidant properties of these oat-based compounds and their ability to neutralise oxidative stress in cells.²

Anti-inflammatory

Inflammation is your body’s normal immune response to injury and pathogens. This is normally a short-term response that helps with your body’s recovery from tissue damage or infection. However, when this becomes a prolonged response, called ‘chronic inflammation’, it can cause problems in the body. Chronic inflammation has been linked to many diseases such as cancer, obesity, diabetes, arthritis, and even neurodegenerative diseases like Alzheimer’s disease.⁴

Oats contain a number of compounds that have been shown to have an anti-inflammatory effect. This can help to prevent or lessen a chronic inflammatory response and its associated diseases. For example, these oat-based compounds cause a decrease in the levels of messenger molecules that trigger inflammation in the body, including TNF-ɑ.¹

These anti-inflammatory compounds include: 

• Polyphenols and phenolic compounds¹
• β-glucan (a type of soluble fibre)⁵
• Avenanthramides³

Protects against cardiovascular disease

Cardiovascular disease (CVD), or heart disease, is largely caused by atherosclerosis. A significant risk factor for CVD is your blood cholesterol level, which is determined by the relative levels of ‘good’ cholesterol (made up of high-density lipoproteins, HDL) and ‘bad’ cholesterol (made up of low-density lipoproteins, LDL).

Oats can help to reduce your risk of developing CVD through their observed effect on lowering the level of ‘bad’ cholesterol in your blood. This is largely attributed to the presence of β-glucan, which is thought to block the absorption of cholesterol in the digestive tract and can also help to reduce blood pressure.¹ A meta-analysis of 28 epidemiological studies showed that eating 3g of oat-based β-glucan provided this protective effect.⁶

Protects against cancer

Oats and their associated nutrients are thought to have an anti-cancer effect.¹ The main compounds that this has been attributed to are β-glucan, a type of soluble fibre found in oats, and oat saponins. Both of these are thought to support the body’s immune system, helping to protect against the formation and development of tumours.^3,7 

In a population-based study, researchers found that the total amount of whole-grain products eaten was associated with a lower risk and occurrence of pancreatic cancer, particularly in middle-aged men.⁸ Similar results have been observed for skin cancer, lung cancer, and colon cancer.¹

The antioxidant and anti-inflammatory properties of oats also help to protect against cancer. Research has shown that up to 25% of tumours are associated with chronic inflammation.³ One of the key antioxidant components in oats, avenanthramides, is thought to be up to 30 times more powerful than polyphenols, which are the main type of antioxidant.³ Many studies have suggested that avenanthramides can induce the death of cancer cells, prevent them from dividing rapidly and forming tumours, and spreading to other parts of the body.³ The latter is a process referred to as metastasis, which plays a significant role in cancer-related deaths.³ This shows the potentially huge health benefits that eating oats can bring.

Weight management

Oats have been suggested as a great addition to your diet in order to help with weight management and to protect against obesity. The soluble fibre in oats, β-glucan, helps you to feel fuller after eating them. β-glucan also helps to slow the process of digestion and therefore helps you feel fuller for longer. 

There is also some evidence suggesting that oat-based β-glucan activates the hormonal signalling involved in making you feel full.¹ This has been associated with reducing body weight, body fat, body mass index (BMI), and even central adiposity.¹ 

Oats are a relatively low-calorie food that is both high in fibre and nutrients, making them a great addition to your diet to help with weight management.

Managing diabetes

Diabetes is a condition where your body’s response to blood sugar is impaired. Oats, and specifically, β-glucan, have been shown to have an anti-diabetic effect,¹ and can help to prevent type 2 diabetes, as well as manage both type 1 and type 2 diabetes.⁶ 

You might hear oats referred to as a ‘low GI’ food, which means it has a glycaemic index that does not cause your blood sugar to rapidly spike after eating it, helping to protect against diabetes. This is attributed to the slow digestion of β-glucan and the effect this has on the digestion of starch.¹ Studies have shown that this occurs in a dose-dependent manner, meaning the more β-glucan you eat, the less your blood sugar levels spike.⁶ 

Notably, while all oats are generally ‘low GI’, some oat-based products exhibit this effect more than others. These are the less processed oat products such as oat groats and oat bran.⁶

Supports your gut microbiome

Oats also contain resistant starches, which have been shown to have a beneficial effect on your gut microbiome.⁹ Your gut microbiome refers to the bacteria and microorganisms that naturally live in your digestive system. Whole grain oats have been shown to help support the growth and maintenance of these bacteria, and especially the growth of beneficial strains of bacteria such as Lactobacillus and Bacteroidetes.⁶ The health of your gut microbiome is thought to support your overall health and help protect against chronic diseases.⁹

Nutritional facts

Macronutrients

Micronutrients

Side effects and other concerns

If you have a gluten intolerance, gluten sensitivity, or coeliac disease, you might assume that you cannot eat oats as part of your diet, but this is not the case. Gluten is a type of protein found in whole grains such as wheat, barley, and rye. Importantly, however, oats do not contain gluten and there is a significant amount of research showing that oats are safe to consume for people with coeliac disease or a gluten intolerance.¹⁰ The problems with oats and oat-based products only occur if they are contaminated by other gluten-containing whole grains. Because of this, it is recommended to only consume oats labelled as ‘gluten-free’.

The high amount of fibre in oats can cause stomach upset if you eat too much. It is recommended that the average adult consumes 30g of fibre a day, which many of us are not getting. But too much fibre can cause bloating, gas, and constipation. These symptoms should relieve themselves within a few days but drinking water and doing light exercise can also help. If they persist, it is best to discuss your fibre intake with a health specialist. To help prevent these symptoms, it is recommended that you slowly increase your fibre intake by 1 to 2 grams per day. 

Summary

Oats are a high-fibre, low-calorie whole grain that can add an abundance of micronutrients to your diet. These not only support your health but have been shown to help protect against diseases such as cardiovascular disease, cancer, and even diabetes. Oats come in many different forms, and the less processed they are, the more nutrients they provide. Even individuals with a gluten intolerance or coeliac disease can benefit from adding ‘gluten-free’ oats to their diet. As a hugely versatile whole grain, they can be eaten for any meal in a range of recipes, you have nothing to lose from giving them a try!