Researchers from the University of Bonn (Germany) recently published the results of two dietary interventions carried out on 68 adults suffering from metabolic syndrome. The objective: to measure the impact of oats on blood parameters.
The secret: a synergy between fiber and microbiota
The first study involved 32 participants randomly divided into two groups. Some had to follow a diet rich in oats for two days and the others, a control diet. The oat group consumed three daily meals totaling 300 g of oatmeal, while the control group ate an equivalent diet without oats. Participants in the oat group were then followed for six weeks after resuming their usual diet.
The second study included 34 participants, some of whom replaced one meal per day with 80 g of oats, while the others maintained their usual diet for six weeks. Blood and stool analyzes were used to assess cholesterol, intestinal microbiota and circulating metabolites.
The results are impressive. By consuming 300 grams of oatmeal per day for just 48 hours, participants saw their LDL cholesterol, known as “bad cholesterol”, drop by 10% and their total cholesterol by 8%.
Even more surprising, these levels remained lower than their initial level during the six weeks of follow-up, even after resuming a traditional diet.
Why are oats so effective? The study highlights two mechanisms:
- Beta-glucan: This soluble fiber, already well known, traps cholesterol in the intestine.
- Ferulic acid: Researchers observed an increase in this phenolic compound in the blood. When our intestinal bacteria break down oats, they produce metabolites that act directly on cholesterol regulation.
However, the study is temperate: more moderate consumption (80 g per day) shows milder effects and depends strongly on the quality of the microbiota of each individual.
“This is a mechanistic study, not a miracle cure”
For Professor Boris Hansel, nutritionist and author of Eating Lightly, which is published in Pocket Edition today, you need to know how to read between the lines. If the study is of a very high standard, on its own terms, it should not be misinterpreted.
“This study is not of interest in showing that food lowers cholesterol, this has been known for decades. Its interest is mechanistic: it is interested in the mechanisms by which we obtain this reduction. This is not to say that when we eat oatmeal, we have a miracle effect”
The professor reminds that to obtain a therapeutic effect, the doses must be large (around 80 g of flakes or 3 tablespoons of bran per day). Which is not always easy on a daily basis. Above all, he warns against catchy titles:
“It’s salesy but misleading. The effect is immediate at very high doses, but the authors did this to measure biochemical reactions, not to conclude that you should eat 300 grams of oats per day and eat nothing else.”
In practice: how to protect your arteries on a daily basis?
To lower your cholesterol naturally, oats are just one pillar among others. Professor Hansel recommends a diversified approach, inspired by the famous Portfolio diet:
- Almonds and walnuts. Consuming 30 to 40 g of oleaginous fruits per day is simple to implement;
- Oat bran. Often preferable to flakes because they are less rich in carbohydrates. “One to two tablespoons, supplemented with soluble fiber (fruits, vegetables, barley), is already good.”
he specifies.
Caution for diabetics: Pay attention to the glycemic index of oatmeal, especially if they are consumed as very cooked porridge (porridge).
Finally, underlines Professor Hansel, these dietary measures should not push patients to stop their medical treatment without specialist advice. “Under no circumstances can anyone who has an indication for a medication replace the medication with oats. It’s less powerful and, in real life, it’s not realistic” he concludes.