Whole Grain Health Benefits

In this Article (Index)

• What is Whole Grain?
• Grain
• Whole Grain
• Refined Grain
• Whole Grain Health Benefits
• Dietary Guidelines on Whole Grains
• Minimum Daily Intake of Grains
• Sources of Whole Grains
• Refined Grains are everywhere
• Americans and their Whole Grain intake
• Whole Grain in the American diet
• Small Changes Can Improve Your Health
• Not all whole grains are the same
• Closing Comments

What is Whole Grain?

Grains

Grains are the edible seeds of different species of grass-like plants that have been used since prehistoric times as food. Mankind learned how to domesticate these plants and invented agriculture 10,000 years ago; it also found how to improve their yield and hardiness against disease and drought.

Grains are obtained from rice, wheat, rye, barley, sorghum, millet, oats, and corn. Other plants like quinoa, amaranth, and buckwheat, known as pseudo-cereals, also produce grains.

Grains consist of an inner edible kernel that is protected by a tough outer shell or husk.
The kernel is the whole grain, with an outer layer known as bran that acts as a protective shell for the inner part of the husk called endosperm, which provides nutrients for the germ and protects it. The germ is the embryo that will develop into a new plant if the grain is sown.

Each of them contains nutrients and phytochemicals: the bran contains fiber and carbohydrates, and some protein, the endosperm which accounts for over 80% of the mass of the kernel is rich in carbohydrates, with some fiber and protein. The germ has the highest protein content and also contains fiber, carbohydrates, vitamins, minerals, and fatty acids. The image above shows a grain kernel and its elements. (4)

Whole Grain

Since antiquity, grains were pounded with stones to remove the inedible husk and crush the kernel into smaller groats that could be cooked easily. Later hand-powered saddle-shaped stone grinders were used for this purpose and coarse whole-grain flours were produced. Bran, germ, and endosperm were milled into whole-grain flour. Technology advanced, and gristmills with large, flat, round stones were laid one on top of the other, one fixed and the other rotating, powered by water, wind, or animals were used to mill flour in larger amounts.

Until the late 1800s, flour was milled with these millstones, and this process couldn't separate bran or germ from the endosperm, and flour had a grayish-white color.

Refined Grain

However, around 1875 steel mills with rollers were introduced, and these could remove the bran and germ resulting in a whiter flour, a refined grain flour.
As it didn't contain the germ oil it had a longer and more stable shelf life. Steel milling was more efficient and cheaper; it led to the closure of small-scale stone mills. The public embraced the luxurious white flour.

Lacking bran and germ, these refined flours lost most of their mineral, vitamins, healthy fats, and almost all of their fiber. The poor segments of the population whose diet consisted of cheap grain-based foods began suffering from vitamin and nutrient deficiencies.

To eradicate these deficiency-based illnesses, in 1941 the U.S. mandated the enrichment of white flour-based food with iron, niacin, thiamin, and riboflavin.

Nowadays, refined flour is found in the processed foods that make up the American diet. These processed foods contribute to the increasing prevalence of obesity, type-2 diabetes and, heart disease.

Whole Grain Health Benefits

The nutrient and vitamin deficiencies experienced in the early 1900s are just one example of the effects of consuming refined grains instead of whole grains. The enrichment process may have eliminated that issue but didn't compensate for the other negative effects of refined grain.

Several studies have shown that eating whole grains vs. refined grains has positive health effects: they protect against cardiovascular disease, diabetes, cancer, and obesity. (7)

How do whole grains protect our health?

The protective effect is due to a combination of factors, that exceed the individual effects of isolated nutrients:

1. Whole grains contain different types of dietary fiber (soluble, insoluble, resistant starch, and oligosaccharides) that promote gut health, which in turn improves immunity and has anti-inflammatory effects. Fiber also helps regulate intestinal transit and acts upon sugar uptake and cholesterol.
2. Bioactive plant compounds (phytochemicals) like polyphenols are antioxidants, whole grain also contains phytosterols and stanols that exert positive health effects.
3. Minerals, vitamins, and healthy oils are also present in whole grains.

A Reduced Death Rate

Whole grains reduce the risk of mortality

A 2016 meta-analysis (8) using data from 45 studies, investigated the relationship between whole grain intake and the risk of death due to cardiovascular disease, cancer, and all-cause mortality. It found that:

whole grain intake is associated with a reduced risk of coronary heart disease, cardiovascular disease, and total cancer, and mortality from all causes, respiratory diseases, infectious diseases, diabetes, and all non-cardiovascular, non-cancer causes. These findings support dietary guidelines that recommend increased intake of whole grain to reduce the risk of chronic diseases and premature mortality. Aune D, Keum N, Giovannucci E, Fadnes L T, Boffetta P, Greenwood D C et al., (2016) (8)

The authors also state that replacing a small amount of refined grain with whole grain can ward off premature death: "Even moderate increases in whole grain intake could reduce the risk of premature mortality."
They found that eating 90 g/day^✽ of whole grain intake reduced the risk of disease and death as follows:

• Reduced risk of coronary disease by 19%, stroke by 12%, and cardiovascular disease by 22%.
• Total cancer mortality risk was reduced by 15%, all causes by 17%, respiratory disease by 22%, diabetes by 51%, infectious diseases by 26% and 22% for all-non-cardiovascular and non-cancer causes.
• There was no evidence of benefits from refined grains, total grains, white rice, or total rice intake.

^✽90 g of whole grain is equivalent to 2 slices of whole grain bread and one bowl of cereal.

Dietary Guidelines on Whole Grains

Considering the health benefits of consuming whole grains and replacing refined grains with them, most countries have defined a recommended daily intake.

The latest edition of the Dietary Guidelines for Americans (2020-2025)(2) explicitly mentions whole grains, describing them and setting a recommended daily intake.

Grains must be part of a Balanced Diet

The U.S. guidelines include "Grains, at least half of which are whole grain" as part of a balanced diet. (2)

Minimum Daily Intake of Grains

Based on scientific evidence, the recommended intakes for whole and refined grains have been defined as follows:

• 6 oz/day (170 g) or more of Total Grains. Composed of:
  
  • 3 oz/day (85 g) or more, of Whole Grains.
  • Less than 3 oz/day (85 g), of Refined Grains.

Sources of Whole Grains

The 2020-2025 Dietary Guidelines for Americans defines them as "All whole-grain products and whole grains used as ingredients," and provides a list of examples of prepared ingredients: whole-grain cereals and crackers, whole-wheat bread, whole-wheat chapati, popcorn. It also lists some whole grains "amaranth, barley (not pearled), brown rice, buckwheat, bulgur, millet, oats, quinoa, dark rye, whole-grain cornmeal, and wild rice".

Refined Grains are everywhere

Refined grains have been defined as "refined-grain products, and those that use refined grains as ingredients".
They are found in almost all baked products, and savory dishes too: "white breads, refined-grain cereals and crackers, corn grits, cream of rice, cream of wheat, barley (pearled), masa, pasta, and white rice." (2)

Americans and their Whole Grain intake

The good news is that Americans reach the recommended 6 oz per 05 of total grain, but the downside is that 3 out of every 4 eat too many refined grains, and 98% of them don't reach the minimum of 3 oz per 05 of whole grain.

Whole grain makes up less than 16% of the total grain intake when it should be at least 50%.

Data published in 2019 by the Centers for Disease Control and Prevention (CDC) (6) shows dismal figures on whole grain intake in America (2013-2016 values) :

• Whole grains represented only 15.8% of the total grain intake among adults.
• Those 60 and over were more health-conscious and ate 19.7%, higher than the 12.9% of younger adults aged 20 to 39.
• Whole grain intake was lowest among Hispanic adults (11.1%).
• Income was linked to whole grain intake, with higher intake (17.8%) among high-income families vs. 12% in lower-income ones.

It seems that Americans aren't aware of the importance of eating whole grains.

Refined Grain in the typical American diet

Grain forms part of the American diet but its sources are mostly highly processed: roughly 50% of refined grains take the form of mixed dishes such as burgers, tacos, pizza, macaroni and cheese, spaghetti and meatballs, and sandwiches. These dishes also include high-calorie ingredients with fats, salt, added sugar, and other processed ingredients.

Another 20% of the refined grains are sweets and snacks, loaded with sugars, fats, and salt: crackers, pretzels, cookies, cakes, biscuits, and deserts with flour.

The remaining 30% of refined grains are separate food items like rice, pasta, tortillas, bread, pancakes, muffins, waffles, and breakfast cereal. Some of which contain too much salt and added sugars.

Whole Grain in the American diet

Roughly 60% of the whole grain intake comes from crackers and cereals. Only a small proportion of baked and cooked grain and mixed dishes use whole grains as ingredients.

Crackers and cereals are processed foods, and though many are labeled as "whole grain" or use the words "whole grain" in product names, this can be deceptive. The public doesn't read ingredient labels to validate these claims. (3)

40–50% of the respondents from a national survey panel could not correctly distinguish between foods that contained all or more than half of the grains as WGs [Whole Grains] and those that contained a little amount of WGs Du, Mengxi, et al., (2022) (3)

Small Changes Can Improve Your Health

According to the U.S. Dietary Guidelines, shifting from a refined loaf of bread to a whole-grain one, or consuming brown rice instead of whole rice can improve your whole-grain intake and lower the amount of refined grain at the same time.
This suggestion is also put forward in a study suggesting that "the largest health benefit might be achieved simply by shifting people from low or no intake of whole grains to an intake of just one serving 16 g/day, such as 16 g of whole grain wheat, or 30 g product/day, such as 30 g of whole grain wheat bread." (4)

Switching to a whole grain cereal with less added sugars and sodium will also improve your health.

Not all whole grains are the same

Americans get most of their whole grains from breakfast cereal and crackers. Other sources are whole grain cookies, biscuits, and cereal bars. Many of these foods are laden with processed ingredients, fats, salt, and added sugar.

There are healthier options for adding whole grains to your diet.

Whole-grain bread, whole-grain oatmeal, and steel-cut oats are easy to add to your balanced diet.

Dishes that include boiled brown rice, barley, quinoa, or amaranth, either cold in salads, or hot in soups, risottos, or as a side with fish, chicken, or beef.
Use whole grain flour instead of refined flour in meatballs, and patties. Add bran to your regular breadcrumbs (oat or wheat bran works fine), and use whole-grain breadcrumbs.
Bake your own cookies, muffins, pancakes, and cakes replacing refined four with whole grain flour.

Whole Grain Labels can be misleading

As mentioned further up, the term "whole grain" on food labels can be misleading. Many ultra-processed foods pose as healthy "whole grain" foods. For example, one cereal brand lists the following ingredients: "Whole Grain Wheat, Corn Bran, Modified Wheat Starch, Color Added, Guar Gum, Cellulose Gum, Salt, Baking Soda, Sucralose. Vitamins and Minerals: Calcium Carbonate, Vitamin C (sodium ascorbate), Iron and Zinc (mineral nutrients), A B Vitamin (niacinamide), Vitamin B6 (pyridoxine hydrochloride), Vitamin B1 (thiamin mononitrate), Vitamin B2 (riboflavin), A B Vitamin (folic acid), Vitamin B12." This brand doesn't contain added sugars, other brands contain 5 g or 6 g of added sugars.

A leading "whole grain" cereal bar whose label reads "made with 8g WHOLE GRAINS" has 48 ingredients! And contains 12 g of added sugars (dextrose, fructose, sugar, inverted sugar), plus added fats (soybean oil, glycerin, and glycerides).

Ethical Whole Grain Labeling

The European "Project WholEUGrain" proposes that the designation "whole grain" should be reserved for specific food categories like pasta, bread, and breakfast cereals, which are regular elements in a healthy balanced diet, and that whole grains should refer to the main ingredient of the food avoiding using the term if less than 50% of its dry matter isn't whole grain. It stresses that consumers regard "whole grain" labeled food as healthy and therefore these foods "should meet accepted standards for healthy foods, e.g. nutrient profiles on salt, fat and sugars."

The National guidance in Scandinavian countries (Denmark, Norway, and Sweden) uses a similar concept, where "whole grain" refers to the grain itself (brown rice, or oats) while whole grain foods must contain a minimum amount of whole grain cereals. Whole grain products carry a label, the "Keyhole symbol" that ensures compliance with this regulation: soft bread should contain at least 25% whole grain, crisp bread, pasta, breakfast cereals, and oatmeal at least 50% whole grain, and flours, flakes, and kernels must be 100% whole grain. (5)

Chose Variety and Less Processed Options

Since cereals differ in their nutrient content (protein, fats, carbohydrates), fiber, minerals, vitamins, and phytochemicals, the processing of these whole grains during washing, husking, milling, steaming, rolling, grinding, flaking can alter their properties, it is a sensible approach to include a wide variety different whole grains in different forms to ensure an optimal health effect. (5)

Closing Comments

Whole grains are good for your health and will help reduce the risk of dying young. You should eat at least 6 oz per day of total grain, and whole grain should add up to at least 3 oz.

Whole grains are good for your health and will help reduce the risk of dying young. You should eat at least 6 oz per day of total grain, and whole grain should add up to at least 3 oz. Americans eat far too many refined grains and too little whole grains. The sources of whole grain are mostly breakfast cereal and crackers, both of which have the disadvantage of being highly processed foods, with many ingredients, added sugars, and sodium.

Using a variety of whole grains in dishes, and replacing refined grain foods with whole grain products are the best ways to add more whole grains to your diet. Try brown rice instead of white, whole grain bread instead of regular refined grain bread. Use whole-grain pasta, and whole-grain flour when you bake.