Reviewed by dietitian Jessica Ball, MS, RD
Getty Images. Food design.
Main points
-
Cutting out ultra-processed foods improves weight, cholesterol and insulin sensitivity.
-
Both meat-based and vegetarian diets provide similar metabolic health benefits.
-
Older adults naturally eat fewer calories when diets focus on whole foods.
We all want to live a long life, but what is living? healthy life? The concept of “healthspan” refers to the years we spend in good health, free from chronic disease. This is a goal most of us share, and our metabolic health plays a role in achieving it. As we age, our cardiometabolic function, which includes things like blood sugar control and cholesterol levels, often declines.
In a recently published study Clinical nutrition Provides compelling evidence on how dietary changes can extend health span.
How was the study conducted?
South Dakota State University researchers discovered how diet quality affects metabolic health in adults age 65 and older. They designed an 18-week, randomized controlled trial where they provided participants with all foods. This controlled feeding approach allowed them to accurately track what everyone ate.
The 36 participants were divided into two groups, each following one diet for eight weeks before switching to the other. Both diets were designed to align with the previous Dietary Guidelines for Americans, 2020-2025, but they differed in their primary protein source:
-
A omnivorous diet Featuring minimally processed lean pork as the main source of animal protein. The diet was designed to be plant-forward, with lots of vegetables, fruits, whole grains, and dairy products like yogurt and milk, as well as eggs. No other meat or poultry was included at this stage, and all dishes avoided added preservatives or artificial ingredients.
-
A lacto-ovo vegetarian diet Concentrate on pulses as the primary protein source. This pattern included beans, chickpeas, split peas and a variety of lentil-based dishes, dairy (such as cottage cheese, strained (Greek-style) yogurt or milk), eggs, vegetables, fruits and whole grains. Like an omnivore diet, all ingredients were minimally processed and foods were prepared without artificial additives.
The most important part of the study was that both diets significantly reduced the amount of ultra-processed foods (UPFs) consumed by the average participant. At the start of the study, about 50% of participants’ daily calories came from UPF. During the intervention, it decreased to only 11 to 14%. During the study, researchers tracked key health markers such as body weight, body fat, blood sugar, cholesterol and levels of certain hormones that regulate metabolism.
What did the study find?
The results were surprisingly consistent in both diet groups. Despite being told to restrict calories, participants naturally ate fewer calories and experienced health improvements. This suggests that the benefits were not about choosing meat or pulses, but rather about discarding many ultra-processed foods in favor of whole, minimally processed foods.
Here are some key findings:
-
Weight loss: Participants lost an average of 3.8 to 4.4 kilograms (about 8 to 10 pounds) during the study without deliberate dieting.
-
Reduced Fat: Visceral fat, which is the harmful fat that surrounds the organs, was reduced by about 13%. Total body fat also decreased significantly.
-
Improved insulin sensitivity: Insulin resistance, a precursor to type 2 diabetes, was reduced by 24%. This means that participants’ bodies improved blood sugar management.
-
Better cholesterol levels: Participants saw significant reductions in total cholesterol and LDL (“bad”) cholesterol—those reductions that can reduce the risk of heart disease.
-
Favorable Hormonal Changes: Studies have noted changes in two key metabolic hormones. Increased FGF21, a hormone linked to energy regulation and longevity. At the same time, leptin, a hormone that signals fullness and is linked to body fat, decreased.
boundaries
While these results are exciting, it is important to consider some limitations. First, the study included only 36 participants (a relatively small sample size), making it difficult to draw general conclusions for all older adults. Additionally, the majority of participants were white, college-educated, and lived in rural areas in the Midwest, limiting the extent to which the findings may apply to a more diverse or urban population. Another limitation is the relatively short duration of the 18-week study, so we do not know whether these improvements are sustained over several years. Larger, longer, and more diverse studies are needed to confirm these findings and understand their long-term impact.
How does this apply in real life?
The findings of this study show that you don’t have to follow a strict, restrictive diet to improve your health. The main thing is to focus on diet Quality. Ultra-processed foods such as packaged snacks, sugar-sweetened beverages, fast food and ready-to-eat meals are engineered to be tasty but often lack essential nutrients while being a source of added sugar, unhealthy fats and excessive salt.
By replacing these ultra-processed items with whole or minimally processed foods, you can make a big impact on your well-being. Studies also show that you can get these benefits from different dietary patterns, whether you eat meat or prefer a vegetarian lifestyle. The common thread is an emphasis on whole foods, which can help you get the nutrients you need every day.
To reduce UPFs in your diet, you can swap your ultra-processed snacks for a handful of nuts, a piece of fruit, or some strained (Greek-style) yogurt. You can also cook a lot at home: preparing your own food gives you complete control over the ingredients.
Our experts
This is published in a recent study Clinical nutrition investigated the effects of two nutrient-dense diets that both focused on reducing the intake of ultra-processed foods. Over 18 weeks, participants experienced significant benefits, including weight loss, reduced body fat, improved cholesterol levels and increased insulin sensitivity, regardless of whether their protein source was meat or pulses. These improvements appear to be driven by a shift to minimally processed foods and cutting out packaged, nutrient-poor alternatives.
The research gives a clear and encouraging message: improving your metabolic health and extending your health are within reach. While diet is only one piece of the longevity puzzle, it plays an important role. By focusing on a diet rich in whole, nutrient-dense foods and reducing ultra-processed products, you can support your body’s ability to function optimally.
Read the original article on EatingWell
