Browse the evidence

Eight weeks of resistance training significantly improves phase angle, a marker of cellular health, in obese older women, independent of significant changes in body fat percentage.

If you are an older woman with obesity, engaging in resistance training for just 8 weeks (3 times a week) can significantly improve your cellular health, as measured by phase angle. This improvement happens even if you don't lose much body fat. Focus on performing 8 exercises with 3 sets of 8-12 reps, progressively increasing the weight as you get stronger, rather than just focusing on the number on the scale.

Implementing a government-supported voluntary national sugar reduction policy targeting packaged foods and beverages results in significant long-term health gains, including reduced cardiovascular disease and diabetes incidence, and generates net cost savings for society.

Supporting government-led initiatives to reduce added sugar in packaged foods and beverages can significantly improve public health and reduce healthcare costs. This involves encouraging industry reformulation to meet specific sugar reduction targets, particularly for sugary drinks.

Time-restricted eating (8-hour window) combined with resistance training improves upper-body high-speed strength (peak force and dynamic strength index) compared to habitual diet, while potentially impairing lower-body explosive performance.

If you are training for upper-body explosive power (like throwing or punching), an 8-hour eating window combined with heavy resistance training may boost your performance more than eating normally. However, if your goal is lower-body explosiveness (like jumping or sprinting), sticking to your normal eating schedule might yield better results. Body composition changes (fat loss) were similar in both groups.

Pharmacologic weight loss medications are effective only when used as adjuncts to lifestyle modifications; discontinuation of medication without sustained lifestyle changes leads to inevitable weight regain.

If you are prescribed a weight loss medication, understand that it is not a cure. It works best when you simultaneously adopt dietary changes and physical activity. If you stop the medication without having established sustainable lifestyle habits, you will likely regain the weight. The drug is an adjunct, not a substitute.

In resistance-trained men, low-load (20 RM) and moderate-load (10 RM) resistance training produce equivalent improvements in maximal strength and body composition when total load lifted is equated and sets are performed to volitional failure.

If you are an experienced lifter, you don't need to grind out heavy 1-5 RM reps to get strong or build muscle. You can use lighter weights (around 20 RM) as long as you take every set to near-failure and match the total amount of weight you lift (sets x reps x weight) to what you would do with heavier weights. This allows for strength and muscle gains similar to heavy training, potentially with less joint stress.

Licensed weight-lowering pharmacotherapies (GLP-1RAs, naltrexone/bupropion, phentermine/topiramate) improve self-reported physical function, but do not significantly improve objectively measured physical function, cardiorespiratory fitness, or physical activity levels.

If you are using FDA/EMA-approved weight loss medications, expect improvements in how you feel you function in daily life (self-reported physical function). However, do not expect these medications alone to significantly boost your actual exercise capacity, VO2 max, or daily activity levels without dedicated exercise training. The benefits are modest and primarily subjective.

In individuals with overweight or obesity at high risk of type 2 diabetes, a trajectory of weight loss followed by weight regain results in a net loss of fat-free mass (FFM) despite fat mass (FM) returning to baseline levels.

If you are overweight or obese and have experienced a cycle of losing weight and then gaining it back, be aware that your body composition may have worsened even if your weight is back to where it started. Specifically, you may have lost muscle mass (fat-free mass) while regaining fat. To counteract this, prioritize resistance training and adequate protein intake during any future weight loss attempts to preserve muscle, as simply returning to your starting weight does not restore your previous body composition.

A trajectory of weight gain followed by weight loss results in a net gain in fat mass (FM) despite fat-free mass (FFM) returning to baseline levels.

If you have gained weight and then lost it back to your starting weight, your body composition may not be the same as it was before. You may have more fat and less muscle than you did initially. To ensure you are maintaining a healthy body composition, incorporate strength training and monitor body composition metrics, not just total body weight.

Drop-set training on leg extensions produces greater non-uniform hypertrophy in the proximal and mid-rectus femoris compared to traditional training, while yielding equivalent strength gains and no differential hypertrophy in the vastus lateralis.

If your goal is to specifically target the Rectus Femoris (the muscle in the middle of your thigh) using leg extensions, using drop sets (reducing weight after failure) may yield better growth than standard sets. However, do not expect this to make you stronger or grow your Vastus Lateralis (outer thigh) any more than standard training would. For general strength and overall quad size, standard training is equally effective and likely less fatiguing.

Diet-induced weight loss reduces left ventricular mass (LVM) in adults with overweight or obesity, whereas adding moderate-to-vigorous physical activity (≥150 min/week) to diet-induced weight loss preserves LVM.

If you are overweight or obese, losing weight through diet alone will reduce your heart's muscle mass. However, if you combine that diet with at least 150 minutes of moderate-to-vigorous exercise per week, your heart muscle mass is preserved. Both outcomes may be favorable, but preserving heart mass through exercise might be a beneficial adaptation alongside weight loss.

Higher body mass index (BMI) acts as a causal agent for a broad range of health outcomes, including type 2 diabetes, ischemic heart disease, high blood pressure, and various cancers, as demonstrated by Mendelian randomization studies.

Maintaining a healthy body weight is not just about aesthetics; it is a direct causal factor in preventing serious diseases like heart disease, diabetes, and certain cancers. While BMI is an imperfect measure, keeping it within a healthy range reduces your risk. If you have obesity, lifestyle changes, medical interventions, or in severe cases, surgery, are effective ways to reduce this risk.

Bariatric surgery significantly reduces all-cause mortality, disease-specific mortality (cancer, cardiovascular, diabetes), and major adverse cardiovascular events (MACEs) in patients with severe obesity compared to matched non-surgical controls.

For individuals with severe obesity, bariatric surgery is a highly effective intervention for reducing the risk of death from cancer, heart disease, and diabetes, as well as preventing major cardiovascular events. It offers superior long-term outcomes compared to lifestyle changes alone for this population. Patients should discuss these benefits with their healthcare providers to determine if they are candidates.

Regular physical exercise prevents age-related skeletal muscle dysfunction, including loss of strength and mitochondrial capacity, by inducing structural remodeling and metabolic adaptations.

Start or maintain regular physical activity, combining aerobic and resistance exercises, to protect your muscles from age-related decline. This is one of the most effective ways to maintain strength, mitochondrial health, and metabolic function as you age.

GLP-1 receptor agonists for obesity treatment cause significant loss of lean body mass (approximately 20-25% of total weight reduction in men and 10-15% in women) and bone density, particularly when rapid weight loss occurs without structured resistance training.

If you are taking a GLP-1 medication for weight loss, you will likely lose some muscle along with fat. To protect your strength and metabolism, you must engage in resistance training (weight lifting) and ensure you are eating enough protein. This is especially important if you are losing weight quickly.

Low-carbohydrate diets are effective for short-term glycemic control and weight loss in T2DM, but benefits often diminish after 12 months and are largely attributable to weight loss rather than carbohydrate restriction itself.

You can try a low-carb diet (50-100g carbs/day) to improve blood sugar and lose weight in the short term. However, be aware that these benefits often fade after a year, likely because you've lost weight. Ensure you are getting enough fiber and monitoring your cholesterol and kidney health.

Responsiveness to resistance training for one outcome (e.g., strength) is not necessarily associated with responsiveness for other outcomes (e.g., glucose metabolism or blood pressure), indicating outcome-specific responses.

Do not assume that getting stronger will automatically fix your blood sugar or blood pressure. If your strength improves but your metabolic markers do not, you may need to add specific interventions (like dietary changes or different exercise types) to address those specific risks.

Regular physical activity, including aerobic, resistance, balance, and dual-task training, reduces the risk of dementia and cognitive decline by enhancing neurogenesis, improving cerebral blood flow, and increasing brain-derived neurotrophic factor (BDNF).

Aim for 150-300 minutes of moderate aerobic activity (like brisk walking) or 75-150 minutes of vigorous activity per week. Add strength and balance exercises twice a week. If you prefer cultural practices like Tai Chi or yoga, these are excellent alternatives that also support cognitive health. Start with what you enjoy and gradually increase intensity.

Current obesity treatments (behavioral, pharmacological, surgical) are effective but often result in weight regain, and their long-term success is limited by unchanged environmental factors.

Obesity treatments are effective but not permanent cures. You need to manage your weight long-term, possibly using a combination of treatments, and be prepared for potential weight regain if you stop.

In older adults with overweight/obesity and type 2 diabetes, losing weight while simultaneously gaining skeletal muscle mass significantly reduces the risk of adverse cardiovascular events compared to weight gain or weight loss accompanied by muscle loss.

For older adults with excess weight and diabetes, simply losing weight on the scale is not enough to protect the heart. You must preserve or build muscle during weight loss. This likely requires resistance exercise combined with adequate protein intake, rather than dieting alone. Losing weight while losing muscle provides no cardiovascular benefit compared to gaining weight.

Among individuals who lose weight, a higher ratio of skeletal muscle mass loss to total weight loss (SMMC/WC) is associated with a significantly increased risk of cardiovascular events, with risk doubling when muscle loss accounts for approximately 50% of weight loss.

If you are losing weight, monitor how much of that loss is muscle. If you lose muscle equal to half your total weight loss, your cardiovascular risk effectively doubles compared to someone who preserves muscle. To mitigate this, prioritize resistance training and protein intake during caloric restriction.

Dietary intake of risk-increasing factors (processed meat, red meat, sugar-sweetened beverages, sodium, saturated fat) has a greater detrimental cardiometabolic impact on younger adults (25-44 years) than on older adults, while risk-reducing factors (fruits, vegetables, nuts, whole grains, PUFA, seafood omega-3) provide the greatest benefit to middle-aged adults (45-69 years).

Your diet matters most right now. If you are under 45, eating processed meats, sugary drinks, and excess sodium is causing the maximum possible damage to your heart and metabolic health. Conversely, if you are between 45 and 69, prioritizing fruits, vegetables, nuts, and whole grains yields the highest health return. Do not wait until you are older to fix your diet; the window for maximum benefit (and minimum harm) is now.

Women experience smaller detrimental cardiometabolic effects from diet than men, as measured by the Adverse Diet-Health Index (IDHIadverse).

Men are statistically more vulnerable to the negative cardiometabolic effects of a poor diet than women. This means men should be particularly vigilant about limiting processed meats, sodium, and sugar, as their bodies may suffer greater immediate harm from these factors compared to women.

Sodium and Sugar-Sweetened Beverages (SSB) are the primary drivers of adverse cardiometabolic health impacts globally, with sodium being the largest contributor in most regions and SSB being the largest in Latin America and the Caribbean.

To improve your heart health, focus on reducing sodium and sugary drinks. In most parts of the world, cutting sodium is the single most effective dietary change you can make. If you live in Latin America or the Caribbean, cutting sugary drinks is likely your highest-impact move. Reducing these two factors will yield the greatest reduction in cardiometabolic risk.

One-anastomosis gastric bypass (OAGB) and Roux-en-Y gastric bypass (RYGB) result in significantly greater reductions in areal bone mineral density (aBMD) at the total hip, femoral neck, and lumbar spine compared to sleeve gastrectomy (SG) within the first year post-surgery.

If you are considering bariatric surgery, know that bypass procedures (OAGB and RYGB) lead to greater bone density loss at the hip and spine than sleeve gastrecty (SG) in the first year. This is likely due to malabsorption of calcium and vitamin D. You should discuss bone health monitoring and supplementation strategies with your surgeon, especially if you choose a bypass procedure.