Browse the evidence

Waist circumference does not predict insulin resistance better than body mass index (BMI); both measures are similarly correlated with insulin resistance.

You do not need to obsess over your waist circumference as a superior health metric. Your BMI is just as good at predicting your risk for insulin resistance. Focus on maintaining a healthy weight overall rather than trying to optimize one specific body measurement.

Higher body mass index (BMI) is associated with increased striatal dopamine tone in humans, as indicated by the differential displacement of low-affinity PET tracers ([11C]raclopride) compared to high-affinity tracers ([18F]fallypride).

This research suggests that higher body weight is linked to higher baseline (tonic) dopamine levels in the brain's reward centers, which may blunt the response to specific rewards. While this paper does not offer a direct intervention, it implies that weight loss might normalize dopamine tone, potentially improving reward sensitivity. However, the causal direction (does weight cause high dopamine or vice versa?) remains unproven in this cross-sectional study.

Pioglitazone, a thiazolidinedione, significantly reduces the risk of developing type 2 diabetes in patients with impaired glucose tolerance and stabilizes beta-cell function, with a favorable cardiovascular safety profile compared to rosiglitazone.

Pioglitazone is a powerful drug that can prevent diabetes and protect pancreatic beta-cells in people with prediabetes. It is more effective than metformin in some studies but can cause weight gain and fluid retention. It is generally reserved for cases where other treatments fail or are not suitable, due to its side effect profile.

Exogenous testosterone administration (200 mg/week) does not alter whole-body energy expenditure, substrate oxidation, or skeletal muscle metabolic gene expression during a severe energy deficit in healthy men.

If you are a healthy man in a calorie deficit and exercising heavily, taking testosterone will not change how your body burns fat or carbs compared to not taking it. It helps preserve muscle mass, but it does not boost your metabolism or fat loss. Focus on your exercise volume and calorie intake for metabolic adaptations.

In individuals with type 2 diabetes who carry the haptoglobin (Hp) 2-2 phenotype, maintaining an HbA1c level below 6.5% does NOT significantly reduce the risk of coronary artery disease compared to levels of 7.0-7.9%.

If you have type 2 diabetes and have the haptoglobin 2-2 genetic variant, aiming for an HbA1c below 6.5% may not provide additional protection against heart disease compared to levels of 7.0-7.9%. This suggests that overly aggressive glycemic control might not be necessary or beneficial for cardiovascular health in this specific group.

Switching from Tenofovir Alafenamide (TAF) to Tenofovir Disoproxil Fumarate (TDF) in women with HIV results in significant weight loss, indicating TDF has weight-suppressive effects.

If you are a woman with HIV and are gaining weight on a TAF-based regimen, ask your doctor about switching to TDF. Studies show this switch can lead to significant weight loss (approx. 1.6 kg) in women, likely because TDF suppresses weight gain compared to TAF.

Classifying individuals by a 'leptin phenotype' (relatively high or low leptin for a given body fat percentage) does not predict differential energy expenditure, metabolic adaptation, or susceptibility to weight change in response to caloric restriction or overfeeding.

Do not rely on fasting leptin levels to predict your weight loss success or failure. Whether your leptin is 'high' or 'low' for your body fat percentage does not appear to change how your body responds to dieting or overeating in terms of energy expenditure or weight change. Focus on sustainable caloric deficits and activity rather than hormonal profiling for prediction.

Postprandial hypotension (PPH), defined as a systolic BP drop of ≥20 mmHg within 2 hours of eating, is an independent predictor of all-cause mortality, syncope, angina, and stroke, particularly in the elderly.

If you experience dizziness, fainting, or significant fatigue after meals, especially if you are older or have diabetes, consult a doctor. This could be postprandial hypotension, a risk factor for stroke and falls.

A 2-week exposure to either a low-carbohydrate (LC) or low-fat (LF) diet does not significantly alter sweet or salty taste detection thresholds or preferences compared to each other.

Switching to a low-carb or low-fat diet for just two weeks will not change your taste buds or your cravings for sweet and salty foods. If you are expecting your food preferences to shift quickly as a result of the diet itself, this short timeframe is likely too short to observe such changes.

Consuming ultra-processed milkshakes high in fat and sugar does not produce a statistically significant average increase in postingestive striatal dopamine release in healthy adults, refuting the hypothesis that such foods elicit drug-like dopamine responses.

The idea that ultra-processed foods trigger a massive, drug-like dopamine spike in your brain is not supported by this research. While individual responses vary, the average brain does not show a significant dopamine release after eating these foods. This suggests that overconsumption is likely driven more by behavioral factors, hunger, and hedonic preference (how much you like/want the food) rather than a fixed, overpowering biological addiction mechanism.

Adiposity (BMI, body fat percentage) is not significantly correlated with the magnitude of postingestive striatal dopamine response to ultra-processed foods, contradicting the hypothesis that obesity blunts this response.

Your body fat percentage does not determine how much your brain releases dopamine when you eat. This study found no link between being overweight and a 'blunted' dopamine response. This is encouraging: it means your brain's reward system is not permanently damaged by your weight, and you can influence your food preferences and intake through behavioral strategies.

DPP-4 inhibitors (Sitagliptin, Saxagliptin, Alogliptin, Linagliptin) are generally neutral for cardiovascular outcomes, with specific agents (Saxagliptin, Alogliptin) associated with an increased risk of heart failure hospitalization.

If you have Type 2 Diabetes and Heart Failure, avoid Saxagliptin and Alogliptin. DPP-4 inhibitors are generally neutral for heart health; prefer SGLT2 inhibitors or GLP-1 agonists which offer proven cardiovascular benefits.

In Japanese subjects, obesity (higher BMI) reduces the numerical incretin effect more significantly than glucose intolerance (T2D or IGT status).

If you have Type 2 Diabetes or pre-diabetes, focus on weight management to improve your body's natural hormonal response to food. In Japanese populations, losing weight improves the 'incretin effect' (how your gut signals your pancreas to make insulin) more effectively than just managing blood sugar numbers alone.

Gastrointestinally-mediated glucose disposal (GIGD), a measure of integrated glucose handling including glucagon suppression, is significantly reduced in Type 2 Diabetes and correlates with obesity.

Managing Type 2 Diabetes involves more than just stimulating insulin; it requires suppressing glucagon. Weight loss helps restore this balance, improving how your body disposes of glucose after a meal.

In elderly patients with type 2 diabetes, maintaining the Triglyceride-Glucose index combined with a Body Shape Index (TyG-ABSI) within an optimal range (specifically avoiding both extremely low and extremely high values) is associated with the lowest all-cause mortality risk.

If you have Type 2 Diabetes, standard weight metrics like BMI might not fully capture your mortality risk. Research suggests that a combination of insulin resistance markers (Triglyceride-Glucose index) and body shape (ABSI) provides a more accurate prediction of health outcomes. Crucially, this risk follows a 'U-shape': both extremely high and extremely low values of this combined index are associated with higher mortality. Therefore, the goal is not simply to minimize these numbers, but to maintain them within an optimal, balanced range, while closely monitoring kidney function (eGFR) as it mediates this risk.

Obesity causes chronic kidney disease directly through adaptive glomerular changes (glomerulopathy associated with obesity) and indirectly by increasing the risk of hypertension and type 2 diabetes.

Maintaining a healthy weight is critical for kidney health. Obesity directly stresses the kidneys through increased blood flow and filtration pressure, leading to scarring (glomerulosclerosis). Weight loss, along with managing blood pressure and blood sugar, is the most effective way to prevent kidney damage.

Hypothalamic gliosis, measured via MRI T2 signal ratios, is positively associated with higher BMI, hypertension, metabolic syndrome, and lower HDL-C, independent of adiposity.

This research suggests that brain inflammation (gliosis) is linked to heart disease risks like high blood pressure and bad cholesterol, even if you aren't overweight. While you can't easily see this on an MRI, it implies that managing metabolic health through diet and exercise might protect your brain's regulatory centers, potentially lowering your cardiovascular risk.

Obesity causes kidney damage through direct mechanisms including glomerular hyperfiltration, increased intraglomerular pressure, and the endocrine activity of adipose tissue, independent of diabetes and hypertension.

Your kidneys are working harder because of your weight. The extra fat tissue releases hormones that increase pressure inside the kidney's filtering units. This constant high pressure damages the filters over time, leading to kidney disease. Managing your weight reduces this internal pressure and protects kidney function.

Elevated Remnant Cholesterol Inflammatory Index (RCII) is independently associated with a significantly higher risk of incident cardiovascular disease (CVD), including heart disease and stroke.

If you are over 45, ask your doctor about your Remnant Cholesterol Inflammatory Index (RCII). It combines your cholesterol levels with inflammation markers to better predict heart disease risk than weight or BMI alone. High RCII indicates a need for targeted lifestyle interventions focusing on both lipid management and inflammation reduction.

RCII partially mediates the association between ABSI and incident CVD, with the mediation proportion increasing across higher ABSI quartiles.

Understanding that inflammation and lipid metabolism (RCII) play a role in how abdominal fat (ABSI) affects heart health can guide more targeted treatments. For those with high ABSI, addressing inflammation may provide additional cardiovascular protection beyond just weight management.

High LDL-C and low HDL-C are more prevalent in women, while hypertriglyceridemia is more prevalent in men in the Iranian adult population.

Lipid profiles differ by gender. Women in this population showed higher rates of low HDL and high cholesterol, while men showed higher rates of high triglycerides. Regular lipid screening is important for both genders, with attention to these specific patterns.

A 12-week combined resistance and high-intensity interval training program significantly increases skeletal muscle gene expression of kynurenine aminotransferase (KAT) isoforms and transcriptional coactivators (PGC-1α, PPARα, PPARδ) in healthy older men, but does not significantly alter circulating plasma kynurenine metabolites.

For older men, a 12-week program combining resistance and high-intensity interval training effectively upregulates the genetic machinery in muscles associated with mood regulation pathways (kynurenine pathway). However, this molecular shift does not immediately result in measurable changes in blood metabolite levels. Consistency is key, as the benefit lies in the local muscle adaptation rather than immediate systemic metabolic shifts.

Intensive lifestyle intervention (ILI) targeting weight loss in adults with type 2 diabetes does not improve cognitive function and may leave a legacy of relative cognitive deficits in subgroups with baseline obesity or cardiovascular disease history, an effect not mediated by changes in leptin or VEGF levels.

For individuals with Type 2 Diabetes, especially those with obesity or heart disease history, intensive lifestyle interventions aimed at significant weight loss may not improve cognitive function and might be associated with relative cognitive declines compared to less intensive support. This decline was not explained by changes in leptin or VEGF. Patients should focus on overall metabolic health and cardiovascular risk reduction, but should not expect cognitive enhancement from weight loss alone, and should monitor for any subjective cognitive changes.

GLP-1 receptor agonists reduce hospitalizations for heart failure (HHF) by approximately 10-11%, although their effect on heart failure with reduced ejection fraction (HFrEF) is neutral or potentially harmful in small studies.

If you have Type 2 Diabetes and heart failure, GLP-1 RAs can help reduce the risk of being hospitalized for heart failure. However, if you have a specific type of heart failure where the heart muscle is weak (HFrEF), the data is less clear, and you should discuss the risks and benefits with your doctor.