Introduction
Eating wholegrain foods can be healthy and enjoyable as part of a balanced diet. But what are whole grain foods, and how can they help our health?
Whole grains are grains at the beginning of their life cycle. Wholegrains contain all 3 parts of a grain, with very little processing.
The 3 parts of the wholegrain are:
- The bran - This is the outside layer, helping to protect the grain
- The germ - This is the small central part of the grain
- The endosperm - This is the middle part of the grain, which contains lots of starch.
Many whole grains are milled into flour and can be used to make bread, crispbreads, pasta, and lots of other whole-grain food products. In comparison, refined grains are grains which are often heavily processed and have the germ and bran taken out. This means refined grains contain fewer nutrients than whole grains and, therefore, have fewer health benefits. Refined grain foods can include white rice and pastas, biscuits, and cakes.
Health benefits of eating whole grains
Eating wholegrains has a vast number of health benefits, including:
- Reducing the likelihood of developing heart attack, stroke, and type 2 diabetes by up to 30% (when eaten alongside a healthy and balanced low-fat diet)4
- Providing a slow release of carbohydrate - wholegrain carbohydrates have both a low glycaemic index, which can help to balance blood sugar levels, and an ability to help you feel fuller for longer, therefore reducing the likelihood of snacking and excessive weight gain5,6
- Wholegrain foods can lower the risk of specific cancers of the digestive system because of the large amount of dietary fibre they contain (this helps to keep the digestive system moving and loosening faecal matter, which makes it easier to pass stools) 7
- Certain whole grains like barley and oats have a special kind of fibre known as beta-glucan (a type of fibre that can be beneficial in reducing cholesterol levels) 1,8
- Wholegrain fibre helps to promote ‘good’ bacteria within the gut ((beneficial in protecting the gut wall)9
- Wholegrains eaten as part of a healthy diet alongside fruit, vegetables, nuts, and seeds may help to reduce the risk of depression as diet is just one part of leading a healthier lifestyle10
Nutrients we can get from eating whole grains
Lots of nutrients remain within the whole grain and are not lost to refining processes. According to The Wholegrains Council, whole grain foods often have 25% more protein and increased amounts of other essential nutrients that we need every day, including:
- Dietary fibre - contained in large amounts, it helps with a variety of roles within the body, including promoting healthy digestion and reducing cholesterol levels and cancer risk7, 8
- B vitamins - included within the bran and the endosperm of the whole grain, B vitamins include 8 water-soluble vitamins which can help to balance energy levels and improve brain function11
- Essential fatty acids (omega-3) - mostly contained within the sperm, omega-3’s are a type of healthy fat which can help reduce the risk for heart disease12
- Antioxidants - combat free radicals found within the body and therefore help reduce inflammation and cancer risk13
- Magnesium (Mg) - Mg content of wholegrains is fairly high, and positively impacts insulin sensitivity and reduces the risk for type 2 diabetes14
How to include whole grains in our diet
Naturally occurring whole grains include:
- Rye
- Oats
- Buckwheat
- Brown rice
- Millet
- Whole wheat
Sometimes it may be hard to know if a food contains wholegrain. Some products may look like they are made of wholegrain because of their colour; for example, a loaf of brown bread may look like a whole-grain product. However, brown-coloured products are often artificially coloured with syrup, so it is best to look at the packaging to confirm the whole grain content of an item.
When looking for wholegrain food items, make sure to:
- Search for foods that are labelled with ‘whole’ in front of their name
- Some countries use the whole grain stamp for foods which are wholegrain. Look out for a sheaf of grain graphic on a yellow background bordered by a black line
- Look at the ingredients and check that grains are high on the list. Foods which contain less wholegrain often have grains lower down on the list. Foods which contain 100% wholegrain may say 100% whole or 100% wholewheat
- Many foods are naturally wholegrains. Look out for foods like oats and wild rice types like brown rice
To include more wholegrain within your diet, you can:
- Use wholegrain flour instead of white flour when baking
- Eat wholegrain breakfast cereals, for example, shredded wheat or porridge.
- Replace white bread with whole-grain bread.
- Eat whole grain snacks such as plain popcorn or rye crispbreads.
- Use wholegrain rice in replace of white rice
- Try a range of wholegrains to help you understand your likes and dislikes (this will also increase the number of servings that are being consumed per day)
- Try to pick starchy foods based on their whole grain content to replace refined grains with whole grain alternatives.
Although many people may think eating wholegrains will break the bank, this is not the case as many whole grain foods are often as cheap or even cheaper than their refined food alternatives. This is particularly true for naturally occurring wholegrains like rye.15
How much is enough?
Dietary guidelines for gluten intake vary per country. However, many experts recommend 3-5 servings of whole grain products to be eaten per day for everybody aged 9 years and upwards, or approximately half of your intake of grains as whole grains.16
Serving sizes can vary depending on different wholegrain foods. A serving size can also depend on your age. Adult serving sizes are recommended as:
- 2-3 heaped tablespoons of cooked wholegrain rice or wholegrain pasta
- One heaped tablespoon of wholegrain flour
- Two oatcakes, crispbreads or rice cakes
- One slice of wholegrain toast or bread
Recommendations for other age groups can be found in the 2015 dietary guidelines for Americans.
Side effects and how much to consume
Some whole grains may cause unwanted side effects for those that have a disease called coeliac disease - an autoimmune disease which means the body has a pro-inflammatory reaction to gluten, a protein found within some grains. However, many whole grain foods are naturally gluten-free like quinoa, corn, wild rice, millet and teff.17,18
Whole grains are far more likely to produce positive health benefits compared to side effects for most of the population. Furthermore, the American population only consumes 16% of whole grain as a percentage of their total grain intake per day. Therefore, it is far more likely to be consuming less wholegrain than overeating wholegrain foods.19
Summary
Consuming whole grains as part of a healthy, balanced diet can reduce the risk of disease and have a variety of health benefits. Health benefits may include weight loss, disease control, protecting the gut, and reducing cholesterol levels. In addition, whole grains can help provide the required nutrients to the body, which can help the body function more effectively. The overall quality of a person’s diet needs to be considered, and the benefits of whole grains are most likely to be seen when incorporated into a healthy diet.
For some groups of people, some whole grains may cause pro-inflammatory reactions. However, for the majority of people, whole grains should be added to the diet. Different countries have different guidelines for the amount that should be consumed daily, but the general consensus among experts is that 3-5 servings of whole grain food products per day will help produce positive health benefits. Therefore, it is recommended that those who can incorporate more whole grains into their diet should do so.
References
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- Reynolds A, Mann J, Cummings J, Winter N, Mete E, Morenga LT. Carbohydrate quality and human health: a series of systematic reviews and meta-analyses. The Lancet [Internet]. 2019 Feb 2 [cited 2023 Feb 22];393(10170):434–45. Available from: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(18)31809-9/fulltex
- Sacn carbohydrates and health report [Internet]. GOV.UK. [cited 2023 Feb 22]. Available from: https://www.gov.uk/government/publications/sacn-carbohydrates-and-health-report
- Sanders LM, Zhu Y, Wilcox ML, Koecher K, Maki KC. Effects of whole grain intake, compared with refined grain, on appetite and energy intake: a systematic review and meta-analysis. Adv Nutr. 2021 Jul 30;12(4):1177–95.
- Ag H, R S, Lm L, Nd F, Bi G, E L. Whole grain and dietary fibre intake and risk of colorectal cancer in the NIH-AARP Diet and Health Study cohort. The American journal of clinical nutrition [Internet]. 2020 Sep 1 [cited 2023 Feb 22];112(3). Available from: https://pubmed.ncbi.nlm.nih.gov/32619213/
- Sima P, Vannucci L, Vetvicka V. Β-glucans and cholesterol(Review). International Journal of Molecular Medicine [Internet]. 2018 Apr 1 [cited 2023 Feb 22];41(4):1799–808. Available from: https://www.spandidos-publications.com/10.3892/ijmm.2018.3411
- Mena P, Bresciani L. Dietary fibre modifies gut microbiota: what’s the role of (Poly)phenols? International Journal of Food Sciences and Nutrition [Internet]. 2020 Oct 2 [cited 2023 Feb 22];71(7):783–4. Available from: https://doi.org/10.1080/09637486.2020.1826913
- Opie RS, Itsiopoulos C, Parletta N, Sanchez-Villegas A, Akbaraly TN, Ruusunen A, et al. Dietary recommendations for the prevention of depression. Nutr Neurosci. 2017 Apr;20(3):161–71.
- Kennedy DO. B vitamins and the brain: mechanisms, dose and efficacy—a review. Nutrients [Internet]. 2016 Feb [cited 2023 Feb 22];8(2):68. Available from: https://www.mdpi.com/2072-6643/8/2/68
- Harris WS, Del Gobbo L, Tintle NL. The Omega-3 Index and relative risk for coronary heart disease mortality: Estimation from 10 cohort studies. Atherosclerosis [Internet]. 2017 Jul 1 [cited 2023 Feb 22];262:51–4. Available from: https://www.sciencedirect.com/science/article/pii/S002191501730196X
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