Oats and oatmeal are often associated with multiple health benefits, including lowering cholesterol and helping with weight management.
A new study published in Nature Communications suggests that following a short-term diet based almost entirely on oats may help reduce cholesterol levels, particularly among people with metabolic syndrome.
اضافة اعلان
Metabolic syndrome is a cluster of conditions that together increase the risk of coronary heart disease, stroke, and diabetes.
Michelle Routhenstein, a preventive cardiology dietitian who was not involved in the study, said: “This is an interesting and well-designed study, but it requires careful interpretation.”
She added: “When diet is tightly controlled with fewer calories, limited saturated fat, high fiber, and low dietary variety, it becomes easier to observe a rapid drop in LDL (‘bad’) cholesterol. This doesn’t mean oats work when eaten in very large quantities or for just two days, but rather reflects how powerful dietary control can be in a research setting.”
Two-Day Diet Lowers LDL Cholesterol by 10%
This small study analyzed two parallel randomized intervention trials, each involving 34 participants. One group was assigned to consume oats, while the other served as a control group.
The oat group was instructed to eat three oat-based meals per day for two days instead of their usual diet. Each meal consisted of 100 grams of oat flakes cooked in water.
To assess longer-term effects, the two-day intervention was followed by a six-week follow-up period during which participants returned to their regular diet without oats.
The control group consumed standardized meals without oats during the intervention days, but these meals were matched in macronutrient composition to those of the oat group.
In the parallel six-week study, the oat group replaced one daily meal with an oat meal containing 80 grams of oat flakes while maintaining their usual diet. The control group continued their regular diet without oats throughout the six weeks.
All participants had abdominal obesity and at least two additional features of metabolic syndrome, such as high blood pressure, impaired glucose metabolism (prediabetes), or dyslipidemia.
The short-term oat group showed an approximately 10% reduction in LDL cholesterol levels, lost an average of about 4 pounds, and experienced a slight reduction in blood pressure.
Kristin Kirkpatrick, a dietitian at the Cleveland Clinic who was not involved in the study, said: “I think the methodology of this study required a very strict approach—eating the same thing for two full days—which may not be realistic in everyday life.”
She added: “People need variety, and the body needs a variety of vitamins, minerals, antioxidants, and other nutrients.”
Routhenstein explained that changes in cholesterol levels usually occur gradually, saying: “People eat a wider range of foods, adherence varies, weight may change, and metabolic responses differ over time.”
She noted that while such studies are useful for understanding biological mechanisms—such as the effect of beta-glucan on cholesterol absorption—they do not replace the importance of consistent, long-term dietary habits.
Short-Term vs. Long-Term Effects
The effects of the oat-based diet persisted even after six weeks.
Dietitian Marie-Christine Simon said: “Following a short-term, oat-based diet periodically may be a good and acceptable way to maintain cholesterol levels within the normal range and help prevent diabetes.”
The effects of the oat diet were more pronounced in the two-day intervention compared to the six-week intervention.
Nevertheless, the longer intervention—where participants consumed 80 grams of oats daily without other dietary restrictions—still showed modest positive benefits.
Kristin Kirkpatrick said: “Oats have proven to be a powerful addition to a heart-healthy diet, and I often recommend them to my patients who are aiming to lower blood lipids and manage blood sugar levels through diet.”
Tips to Help Lower Cholesterol
Although oatmeal can be a healthy option for lowering cholesterol, there are other well-established strategies.
Routhenstein said: “I advise focusing on sustainable, long-term eating habits rather than short-term diets. Because heart disease develops gradually, daily eating patterns matter most.”
Kirkpatrick added that a healthy diet should include “ample amounts” of plant-based foods and healthy fats.
She explained that a balanced diet should be low in added sugars and focus as much as possible on plant-based proteins. It is also recommended to include wild-caught fatty fish, skinless white poultry, and small amounts of lean red meat.
She said: “Diet plays an important role, but it’s not the only factor. Adequate physical activity, stress management, healthy sleep habits, reduced alcohol consumption, and quitting smoking are all essential.”
Are Fibers the “New Protein”?
The recent trend toward so-called “fiber maximization” has led some people to suggest that fiber has become the most important nutrient, replacing protein.
Sherry Frye, a health and wellness expert, said: “There is growing consumer interest in digestive and gut health, which we’ve observed in recent years.”
She added: “Younger generations recognize that digestive health is linked to better skin and improved cognitive function.”
Despite the growing popularity of fiber, Routhenstein cautioned that fiber should not replace protein. Evidence supports dietary patterns that include adequate protein alongside high fiber intake to support muscle health, metabolism, and heart health.
She said: “Fiber and protein serve different physiological roles. Higher fiber intake is consistently associated with a lower risk of heart disease, better blood sugar control, improved gut health, and reduced overall mortality. However, most adults consume less fiber than the recommended amounts.”
