How many whole grains should you eat each day?

We choose whole-wheat pasta once a week, buy cereal bread for breakfast, and occasionally make a farro salad. But how important is this presence of whole grains in our diet? A meta-analysis published September 15 in the European Heart Journal, which pooled the results of 87 randomized clinical trials, seeks an answer. The researchers' question was specific: what happens to risk factors related to heart health and metabolism as the amount consumed varies?

The conclusion is that increased consumption of whole grains is associated with small improvements across multiple dimensions, including cholesterol, fasting blood sugar, blood pressure, and waist circumference. For most of the indicators examined, the greatest effects were observed around 60-100 grams of whole grains per day, calculated as dry weight. The authors translate this, according to the equivalences used in the analysis, to approximately four to six daily servings of whole grains. This is not a suitable dose for everyone, nor a threshold beyond which the benefits disappear: the available studies are too few, especially at the highest doses, to set a precise limit.

Pay attention to the counting

This is the easiest part to misunderstand. The 60-100 grams isn't the weight of the pasta after cooking, and it doesn't simply indicate the total weight of bread and other products we put on our plate. Research expresses the dry weight of whole grains; bread and convenience products also contain water and may include different ingredients. Therefore, you can't take a 50-gram slice of bread and automatically count it as 50 grams of whole grain. Even the wording "with grains" doesn't, by itself, tell you how much whole grain is present: you have to look at the ingredients list to determine this.

In everyday cooking, this data suggests, above all, looking at the whole day, rather than relying on a single "virtuous" meal. You can choose whole-wheat bread for breakfast, prepare whole-wheat pasta for lunch, or use brown rice and other grains for a salad. You don't need to include all these foods in the same menu: they're options to alternate, even according to your own tastes. The key is to make room for whole grains regularly, often choosing them over their refined counterparts.

Why integrals are different

A grain is defined as whole grain when it retains the three original parts of the grain: bran, germ, and endosperm. Refining removes some of these. This difference affects the food's composition, starting with the presence of fiber and other substances contained in the outer parts and the germ. The analysis considered studies on different grains and whole grain foods; therefore, the overall result does not allow us to conclude that a particular pasta or a single type of bread alone produces the observed effects.

The numbers also help maintain balance. For every 48-gram increase in dry weight of whole grains per day, the analysis found, on average, a reduction of about 0.20 kg in body weight, 0.10 mmol/L in total cholesterol, and 0.82 mmHg in systolic blood pressure, along with smaller changes in other indicators. These results aren't spectacular for any single parameter: the study's interest lies in the fact that the changes involve multiple factors simultaneously.

Finally, there's a crucial distinction. The researchers measured risk factors; they didn't follow individuals to determine how many heart attacks or cases of diabetes were avoided. And the responses weren't identical across all indicators. The "four to six servings" number is therefore a reference drawn from studies, not a prescription to be applied to every meal. The practical part, for those who cook, is simpler: an occasional portion of whole-wheat pasta can be a good dish; to ensure consistency in the choice, we should also consider the bread and other grains we regularly eat.