This is the first article in our new Controversies series where we plan to tackle some of the biggest nutritional myths swirling around the three macronutrients—carbohydrates, fats, and proteins.
The subject of a lot of negative press, whole grains have been a staple of the human diet for centuries.
From the Aztecs and the Incas who ate amaranth and quinoa (a pseudograin), to rice in Asia and wheat and rye in Europe, whole grains have been with us a very long time.
And yet today, whole grains emerge as an enormous nutritional controversy.
Those opposed to whole grain believe it is the enemy, bad for our health and our waistlines. Whole grain proponents argue the exact opposite, believing this group of carbohydrates is a powerful health promoter.
Let’s explore the truth about grains together.
What Is a Grain?
When we refer to grains, we normally talk about cereal grains, which are members of the grass family Poaceae.
Here are some of the most common cereal grains: barley, brown rice, maize, millet, oat, rye, sorghum, spelt, and wheat.
Also included in the definition are pseudocereal grains, which come from broadleaf plant families and include: amaranth, buckwheat, chia, and quinoa.
And What Does ‘Whole Grain’ Mean?
A whole grain is a grain in which all components of grain (the bran, the germ, and the endosperm) remain intact.
Interestingly, a grain can be considered ‘whole’ even when ground into flour.
Whole grain bread, whole grain cereal, and whole grain pasta are all examples of foods that contain ground whole grains. And while these foods are still good for you, eating the whole grains themselves will always be better.
How to Read a ‘Whole Grains’ Label
When it comes to evaluating whether or not a product contains whole grains, you need to read the label carefully. Here are a few guidelines:
- Make sure that whole grains (versus sugar!) are among the first few ingredients listed.
- Verify that there are at least 2-3 grams of fiber per serving.
- Ignore any ‘whole food stamp’ on the box (read the food label carefully instead!)
- Examine the ratio between grams of carbohydrates and grams of dietary fiber; an ideal ratio will be 5:1 or less.
- Avoid products using words like these: enriched flour, white flour, enriched wheat flour, enriched bleached flour, and all-purpose flour.
- Look for the following words instead: whole, rolled, stone ground, sprouted, cracked. For example, whole grain flour, rolled oats, ground-on-stone whole-wheat flour, cracked wheat berries, and bulgur cracked
Why Whole Grains Promote Health
Current scientific evidence associates whole grains with these health benefits:
- Treatment of Hypertension. The daily consumption of whole grains (as part of a healthful, plant-based diet) may be as powerful as high blood pressure medications in battling hypertension. While an analysis of randomized drug trials showed that blood pressure lowering medication reduces the risk of suffering a heart attack by 15 percent and stroke by 25 percent, another study reveals you might get similar results by eating three portions of whole grains a day!
- Protection Against Arterial Plaque Build-up. A study measured the amount of plaque in the carotid arteries of 1000 people over five years. Those who ate whole grains had a slower progression of atherosclerotic disease.
- Reduction in Risk of Premature Death. Using data from 45 studies, researchers calculated that eating 90 grams of whole grains per day reduced the risk of all-cause mortality by 17 percent. A second meta-analysis, which used the data from 14 studies (788,076 participants), showed that those who ate the most whole grains enjoyed a 16 percent reduced risk of all-cause mortality and an 18 percent reduced risk of cardiovascular-related mortality.
The Three Pillars of the Whole Grain Debate
The debate about whole grains rests on the following three claims:
- Claim 1: Whole grains are bad for us because humans are not biologically adapted to eat them. Homo sapiens are 200,000+ years old while the agriculture that produces whole grains is much younger (10,000 years). According to those who are opposed to the consumption of grains, before agriculture came about, humans lived healthfully on a diet of fruits, vegetables, tubers and wild animals. Therefore, we should continue eating like our ancestors and forego whole grains altogether.
- Claim 2: Whole grains are bad for us because they contain phytates, which bind to minerals (iron, zinc, manganese) and therefore ‘steal’ nutrients from our bodies.
- Claim 3: Whole grains are bad for us because they make us fat. Whole grains contain carbohydrates, which the body turns into sugar and then stores as fat. We use grains to fatten livestock, and eating grains will do the exact same thing to you.
Let’s counter these points one by one.
Claim 1: Humans are not biologically adapted to eating grains.
The hypothesis here is that we have only been eating grains for 10,000 years and, as a result, our bodies are incapable of processing grains.
The premise of this pillar does not seem to be true. As a matter of fact, it appears that people who lived in what is now Mozambique may have eaten a diet based on sorghum as far back as 105,000 years ago, Neanderthals apparently consumed grains 44,000 years ago, and there is evidence to suggest that grains were consumed in Europe over 30,000 years ago.
And even if we take this claim at face value, we must extend its logic to other foods. For example, chickens were first domesticated 10,000 years ago in China. Equally, the earliest evidence of domestication of turkeys by Native Americans date to 200 B.C. (far less than 10,000 years ago). Cattle were also domesticated between 8,000 to 10,000 years ago. For this argument to hold up, therefore, those opposed to eating grains should not be eating beef, chicken or turkey either.
Claim 2: Grains are bad for you because of their phytate content.
As we will see, the exact opposite is true.
One of the most fascinating bioactive food compounds around, phytates are naturally found in whole plant foods and are plentiful in whole grains.
Phytates are considered an anti-nutrient because they bind to minerals (e.g. zinc, calcium, and magnesium) and prevent their absorption. However, when analyzed carefully, the ‘anti-nutrient’ effect of phytates seems only to appear when a large quantity of phytates are consumed in conjunction with a nutrient-poor diet. Also, cooking, boiling, fermenting, soaking or germinating whole grains will inactivate phytic acid and free minerals up for absorption by the body.
The consumption of whole grains in recommended amounts seems to have no adverse effect on mineral status whatsoever.
Far from being bad for you, phytic acid appears to be beneficial for our health.
Despite initial concerns that phytate consumption might lead to calcium deficiency and weakened bones, studies show that it may actually protect against osteoporosis.
Finally, and most famously, phytates may protect our bodies against cancer.
Quickly absorbed from the digestive tract, dietary phytates appear to be taken up by the body’s cancers cells and are shown to inhibit the growth of a variety of cancer cells – e.g. leukemia, colon, breast, cervical, prostate, liver, pancreatic, skin, and muscle.
Even better, phytates seem to fight only cancerous cells, leaving the normal cells intact.
Why are phytates so effective in battling cancer?
Through a combination of antioxidant, anti-inflammatory and immune-enhancing activities, phytates block the formation of new blood vessels that might feed the tumors and disrupt pre-formed capillary vessels.
So, the claim that we should not eat whole grains because of their phytate content simply does not stand up; phytates are a powerful health-promoting ally, not the enemy.
Claim 3: Whole grains make you fat.
This pillar is based on the idea that carbohydrates cause obesity because they elevate insulin levels and therefore increase fat storage.
The logic behind this theory assumes that:
- Insulin plays a primary role in making us fat.
- Only carbohydrates elevate insulin levels.
Let’s examine these claims together.
For starters, research shows that body fat is regulated by the brain—not by fat tissue itself or an insulin-secreting pancreas.
The primary role of insulin is to manage the concentrations of nutrients.
When insulin suppresses fat burning, it is normally because there is an abundance of glucose. In other words, insulin ‘tells’ storage tissues to stop burning fat because carbohydrates are available as fuel.
However, if you eat a diet high in fat (and low in carbohydrates), insulin ‘instructs’ your body to burn fat instead of carbohydrates, but it will not dip into your fat stores any more (or any less) than if your diet was based on carbohydrates. As long as the calories consumed are close to or in excess of what you need, fat storage will remain the same.
Another problem is that the carbohydrate-insulin theory also presumes that carbohydrates have some unique relationship with insulin causing the latter to spike.
However, when you examine the insulinogenic index (a measure of how much eating food increases insulin per unit calorie), you see that protein-rich foods like beef increase insulin secretion as much as carbohydrate-rich foods like pasta.
In the end, 3 billion people on the planet live on grain-based diets with little or no obesity.
Whole grains are low in calories (particularly when compared to animal foods), low in fat and high in satiating carbohydrates.
While it is true that a few people are sensitive to some types of whole grains and should avoid them, for most of us whole grains are a health-promoting addition to our diet, especially when the diet is already based on the consumption of whole plant foods.