Are Whole Grains a No-Brainer for Dietary Health?

So many things about dietary guidance foster seemingly endless arguments. Fights about meat, dairy, and saturated fats flare up over and over again. But whole grains seem like something of a safe zone. A recent study tells us they are more satisfying than refined grains. Observational research points to less risk for diabetes, cancer, and heart disease. So are whole grains a no-brainer for dietary health?

Effects on Appetite and Energy Intake

A recent study by Lisa Sanders and colleagues took an exceptionally thorough look at all of the evidence from RCTs to test the effects of whole grains on appetite and energy intake. The questions here are really pretty simple. Are whole grains more satisfying and filling than refined grains? Do they lead a person to eat less?

These are important questions because observational research consistently shows a correlation between eating more whole grains and having a lower risk of obesity.

Unfortunately, the answer was mixed. Yes, whole grain foods do a better job of satisfying a person’s hunger, filling them up, leaving them satisfied with less desire to eat. Yet across all of these studies, the evidence does not support a significant effect on how much a person eats. A significant decrease in energy intake was simply not there in the data.

Why the Mixed Results?

On one hand this might be surprising. If people are filled up by these foods, would they not just naturally eat less? But on the other hand, it’s quite clear that people eat for many reasons other than physical hunger. Just one example is the hedonic hunger, driving a person to eat purely for the pleasure of highly palatable foods. With more hedonic hunger, a person’s risk of obesity appears to rise.

Taking all of this into account, it’s not surprising that whole grains might not have a big effect on how much a person eats, even if they do satisfy physical hunger better.

So Why Favor Whole Grains?

There are two ways to look at whole grains. One is through the lens of good, wholesome food. Whole grains tend to be more nourishing and satisfying. Just about everyone everywhere will tell you that for a healthful dietary pattern, whole grains are best. The guidance is simple. Try to make sure that at least half of the grains you consume are whole grains.

Then there is the marketing lens. Because the consensus to favor whole grains is so strong, food marketers are stepping up with health claims and labels to put a healthy halo on their products. The goal is simple – to coax us to buy and consume more. Recently, the food industry agreed on a global definition for whole grain foods. By that definition, a product needs only 50% of its ingredient to be whole grains.

Marion Nestle offers a different perspective:

“Marketing of whole grains is tricky. The only label that counts is 100% whole grains. Anything other than that is marketing hype.”

She has a point. The veneration of whole grains is not a bad idea. But marketing hype doesn’t help with health outcomes. “Eat more, it’s good for you” does not always lead us to better health.

Click here for the study by Sanders et al. For further perspective on the relationship between dietary health and whole grains, click here.

Grainstacks in the Sunlight, Morning Effect; painting by Claude Monet / WikiArt

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April 12, 2021