Here’s what Tufts experts want you to remember from 2025 about staying active and eating well
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Each year brings new findings that deepen our understanding of how nutrition and lifestyle shape health. In 2025, Tufts experts helped us interpret emerging science and highlight evidence-based strategies on topics that matter. From advances in brain and bone health to new insights on diabetes, fats, and the role of physical activity, these conversations reflected both the breadth of ongoing research and the practical guidance it can provide. As we look ahead to 2026, we first pause to review the themes that defined the past year.
Make a Move
Roger A. Fielding, PhD
Research published and reported on in 2025 reinforces that physical activity and healthy lifestyle changes benefit health in many ways. Whether spread throughout the week or packed into one or two “weekend warrior” sessions, regular movement—150 minutes of moderate activity or 75 minutes of vigorous activity a week—is consistently linked to lower risk of chronic conditions like high blood pressure, type 2 diabetes, and heart disease. Even short bursts of vigorous daily activity—like scrubbing a floor or dashing to catch a bus—may support cardiovascular health.
Importantly, the benefits of physical activity are not exclusive to those who lose weight. Studies we reported on in 2025 suggest physical activity may improve how fat cells function, reduce inflammation, and strengthen the cardiovascular system even in people who see no change on the scale.
Being fit appears to matter more than body size. People with high cardiorespiratory fitness (achieved through aerobic activity) are far less likely to die from cardiovascular disease than those who are unfit, no matter their weight category. Conversely, long stretches of sedentary time increase risk for metabolic problems, even among otherwise healthy individuals.
Taken together, these findings reinforce a simple but powerful message: all movement counts.
Roger A. Fielding, PhD, is a senior scientist in the Metabolism & Basic Biology of Aging directive at the Human Nutrition Research Center on Aging (HNRCA) and professor of biochemical and molecular nutrition at Tufts University’s Friedman School of Nutrition Science and Policy.
The Brain-Body Connection
Kyla Shea, PhD
Several studies published in 2025 underscore that dietary pattern quality, body weight, and lifestyle habits all play important roles in maintaining cognitive function and lowering the risk of dementia.
One long-term study found that people with healthier dietary patterns and less excess abdominal fat in midlife had better memory and stronger brain connections when tested in their 70s. Another study, drawing on data from nearly 200,000 adults, showed that even modest amounts of processed red meat were associated with higher dementia risk—while swapping those foods for nuts, legumes, fish, or poultry was linked to better brain health and less cognitive aging. Some of the beneficial compounds in plants include flavonoids, which are found in foods like tea, apples, and blueberries. We reported on a study that found that, for older adults (especially women) consuming more flavonoid-rich foods was associated with lower risk for frailty, physical decline, or poor mental health.
And lifestyle matters, too. A large U.S. clinical trial found that lifestyle modifications that combined healthy eating with physical activity, social and cognitive activity, and cardiovascular health monitoring boosted brain function over two years in older adults already at risk for decline. It will be important to evaluate whether these benefits are sustained over time.
There’s no single “brain food,” but a balanced, plant-forward dietary pattern—combined with movement, social connection, and heart health—offers promising protection against cognitive decline.
Kyla Shea, PhD, is a scientist in the Diet & Chronic Disease Prevention for Healthy Aging directive at the HNRCA and an associate professor at the Friedman School.
Building Better Bones
Bess Dawson-Hughes, MD
Osteoporosis— characterized by weakened, porous bones—affects over 10 million Americans, with another 43 million at risk. The condition is especially common among women over 65. Fractures from fragile bones can lead to loss of independence, reduced mobility, and even increased risk of death.
As reported in 2025, the U.S. Preventive Services Task Force reaffirmed its recommendation that all women 65 and older be routinely screened for osteoporosis, typically with a DEXA scan. Postmenopausal women under 65 with risk factors—like smoking, low body weight, or corticosteroid use—should talk to their doctor about screening, too.
But prevention doesn’t stop at screening. Proper nutrition is key: Calcium and vitamin D remain essential, while consuming the recommended amount of protein, magnesium, and vitamin K also support strong bones. The ideal diet? More fruits and vegetables, fewer refined grains, and protein in line with recommendations (0.8 grams per kilogram of body weight meets most people’s needs).
Physical activity is equally critical. Weight-bearing and resistance training place stress on the skeleton, signaling bone-forming cells to build stronger, denser bone. Balance-focused activities like tai chi or yoga reduce fall risk, which is the cause of 90% of fractures. Even simple choices—climbing stairs, dancing, or lifting soup cans at home—add up to meaningful protection.
Small, consistent steps in each of these areas can help keep bones strong, reduce fracture risk, and preserve independence well into older age.
Bess Dawson-Hughes, MD, is a senior scientist in the Diet and Chronic Disease Prevention for Healthy Aging directive at the HNRCA and a professor at Tufts University School of Medicine, Endocrine Division.
Type 2 Diabetes Prevention and Management
Richard Siegel, MD
Diabetes affects more than 38 million Americans, with another 97.6 million adults living with prediabetes. While type 1 diabetes is an autoimmune condition that cannot yet be prevented, type 2 diabetes—the most common form, accounting for over 90 percent of cases—is strongly linked to lifestyle factors and, in many cases, can be delayed or even prevented.
Type 2 diabetes develops when the body’s cells stop responding properly to insulin, leading to elevated blood sugar over time. Risk factors include physical inactivity, excess body weight (especially abdominal obesity), and family history. Choosing high-quality carbohydrates like fruits, beans, and whole grains; cutting back on ultraprocessed foods and added sugars; and prioritizing plant-based proteins and healthy fats all support prevention and management. Interestingly, research reported on in 2025 suggests that intake of total sugar (added and naturally occurring in milk and fruit) itself is not directly tied to diabetes risk—but sugar-sweetened beverages and, to a lesser extent fruit juice, are.
Lifestyle changes remain a cornerstone of both prevention and management. Even modest weight loss can improve blood sugar control, and physical activity plays a critical role. Of course, the benefits of nutrition and physical activity go well beyond diabetes prevention.
Richard Siegel, MD, is an endocrinologist who serves as co-director of the Diabetes and Lipid Center at Tufts Medical Center. He is also an associate professor at Tufts University School of Medicine.
Fats that Favor Health
Alice H. Lichtenstein, Dsc
When it comes to dietary fat, the type you choose makes a difference.
In a study of more than 221,000 U.S. adults followed for up to 33 years, the highest butter intake was associated with a 15 percent higher risk of death, while the highest intake of plant-based oils—like olive, canola, and soybean—was associated with a 16 percent lower risk. Researchers estimated that swapping just two teaspoons of butter for plant oil (including seed oils) each day could reduce total mortality by 17 percent.
Similar findings reported on in 2025 indicate that drinking whole milk was associated with higher risk of coronary artery disease and death than choosing low-fat (1%) milk. Since dairy is one of the main sources of saturated fat worldwide, opting for low-fat or fat-free versions may support better heart health.
And, while coconut oil remains trendy, be aware that it’s mostly saturated fat—with more saturated fatty acids than the same amount of butter or beef. Using it occasionally for flavor is fine, but, for everyday cooking, plant oils like soybean, canola, corn, or olive are the healthier choice.
Alice H. Lichtenstein, DSc, is a Tufts University distinguished professor, the Stanley N. Gershoff Professor of Nutrition Science and Policy at the Friedman School, senior scientist and leader of the Diet & Chronic Disease Prevention for Healthy Aging directive at the HNRCA, and editor-in-chief of the Tufts Health and Nutrition Letter.
This article originally appeared in the Tufts Health & Nutrition Letter, published each month by the Friedman School of Nutrition Science and Policy. To get more expert guidance on healthy cooking, eating, and living, subscribe here.
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For more expert guidance on healthy cooking, eating, and living, subscribe to Tufts Health & Nutrition Letter, published each month by the Friedman School of Nutrition Science and Policy.
