Browse the evidence

Using the Glycemic Index (GI) as a primary indicator for carbohydrate quality fails to improve diet quality or Dietary Guidelines adherence because it ignores nutrient density and food context.

Stop using Glycemic Index (GI) labels or lists to guide your daily food choices. The GI ignores nutrient density and doesn't predict how your body reacts to mixed meals. Instead, focus on the Dietary Guidelines for Americans: eat nutrient-dense foods (vegetables, fruits, whole grains, legumes) in appropriate portions. This approach is more reliable for health than chasing low GI numbers.

In patients with type 2 diabetes and recent acute coronary syndrome, a body weight loss of 5% or more is independently associated with a significantly higher risk of all-cause mortality and cardiovascular events.

If you have diabetes and a history of heart issues, losing more than 5% of your body weight without trying is a medical emergency. It often signals worsening heart failure, kidney disease, or other serious conditions. Do not view this weight loss as a success; consult your doctor immediately to investigate the cause.

In patients with type 2 diabetes and recent acute coronary syndrome, a higher baseline Body Mass Index (BMI > 30 kg/m2) is associated with a lower risk of primary cardiovascular outcomes compared to those with a BMI of 26-30 kg/m2.

If you have diabetes and recent heart issues, having a higher BMI (over 30) might actually protect you from cardiovascular events compared to being 'normal' weight. Do not attempt aggressive weight loss unless advised by your doctor, as maintaining your current weight may be beneficial for your heart.

Acute exercise (both HIIT and MICT) results in more phosphosite down-regulation than up-regulation, suggesting that acute exercise involves the inhibition of kinase activity and/or activation of phosphatases.

Exercise doesn't just turn things on; it also turns things off. This balance is crucial for adaptation. Don't assume more activation is always better; regulation (inhibition) is part of the process.

Standard RNA-seq normalization strategies that ignore global changes in total RNA content during resistance training produce counterintuitive, biologically invalid results by failing to account for increased ribosomal biogenesis and tissue mass.

If you are analyzing muscle gene expression after resistance training, do not use standard normalization methods that assume total RNA remains constant. You must account for the increase in total RNA (ribosomal biogenesis) caused by muscle growth, or your results will be biologically invalid and counterintuitive.

Tirzepatide has surpassed semaglutide as the most commonly prescribed first-time GLP-1 RA medication in the US as of September 2025.

Tirzepatide is now the most frequently prescribed first-time GLP-1 medication in the US, overtaking semaglutide. This reflects changing prescribing preferences among physicians.

Lean individuals with Metabolic Dysfunction-Associated Fatty Liver Disease (lean-MAFLD) face a significantly higher risk of liver-related mortality compared to overweight or obese MAFLD patients, despite having equivalent metabolic profiles and similar risks for extrahepatic mortality.

If you are lean but have been diagnosed with fatty liver (MAFLD), do not assume you are safe because you are thin. Your risk of liver-related death is actually higher than that of obese patients with the same condition. Standard weight loss advice, especially rapid loss via drugs, can be dangerous for you because it strips away muscle, which your liver needs. Focus on metabolic health markers (blood pressure, glucose, lipids) and consult your doctor about treatments that preserve muscle mass rather than just focusing on weight loss.

Personalized diet advice based on single or few continuous glucose monitor (CGM) measurements of duplicate meals is unreliable in adults without diabetes because within-subject glycemic variability for identical meals is similar to variability for different meals.

Do not make permanent dietary changes based on a single CGM reading of one meal. Your body's response to the exact same meal can vary significantly from day to day due to factors like sleep, stress, and activity. If you use a CGM, look for broad patterns over weeks (e.g., 'plant-based diets generally lower my glucose') rather than trying to identify specific 'bad' foods based on one spike. Reliable personalization requires aggregating many repeated measurements, not just one or two.

Biliopancreatic diversion with duodenal switch (BPD/DS) and its variants (SADI, TB) provide superior weight loss compared to Sleeve Gastrectomy (SG) and Roux-en-Y Gastric Bypass (RYGB) in extreme obesity, but at the cost of higher early complication rates and malnutrition risk.

For extreme obesity, malabsorptive surgeries like BPD/DS or SADI provide the best weight loss (38%+), significantly better than SG (23%) or RYGB (26%). However, these come with higher early complication rates (12.9% vs 4-8%). SG is safer but less effective for weight loss, making it a good option for older/younger patients or as a first step.

Higher AMY1 gene copy number does not significantly modify the risk of cardiovascular disease or mortality associated with starch intake.

You do not need to test your AMY1 gene copy number to determine your starch intake. Standard moderate starch intake recommendations likely apply to you regardless of your genetic makeup regarding amylase.

Repeated or substantial weight loss (≥5 kg, especially >10 kg or ≥3 episodes) is associated with significantly increased all-cause and cardiovascular mortality in men, but not in women.

If you are a man, be cautious about repeated, large weight loss cycles (especially >10kg or 3+ times). This study links such patterns to higher heart and overall mortality risk. Women in this study did not show the same risk. Focus on maintaining a stable, healthy weight rather than repeated drastic losses, and consult a doctor if weight loss is unintentional.

Repeated weight loss (≥3 episodes of ≥5 kg) is associated with increased all-cause and cardiovascular mortality, regardless of the total amount lost in a single episode.

If you have lost weight 3 or more times (even if each time was 5kg), your risk of heart disease and early death may be higher than if you had never lost weight. Try to maintain a stable weight rather than cycling up and down.

A single acute bout of resistance exercise training (RET) does not induce mitochondrial remodelling (biogenesis, content, or quality control) in either untrained older adults or master athletes within the acute (1h) or delayed (48h) recovery periods.

If you are an older adult or a master athlete, do not expect a single resistance training session to improve your mitochondrial health or biogenesis. While long-term resistance training is crucial for muscle mass and strength, acute mitochondrial remodeling (like building more mitochondria) is not triggered by a single bout of resistance exercise in these populations. Focus on consistency for muscle health, but rely on endurance training for acute mitochondrial signaling responses.

None of the tested dietary supplements (protein, creatine, HMB) significantly increased lean body mass in athletes when combined with strength and conditioning training.

Do not expect supplements like protein, creatine, or HMB to significantly increase your muscle mass on their own. Focus on your training and overall diet. This analysis found no significant benefit for muscle mass from these supplements in trained athletes.

Sleeve gastrectomy is associated with a higher risk of new-onset or worsening gastroesophageal reflux disease (GERD) compared to Roux-en-Y gastric bypass (RYGB).

If you have existing or severe acid reflux, Roux-en-Y gastric bypass is likely a safer choice than sleeve gastrectomy, as the sleeve procedure carries a higher risk of causing or worsening reflux.

Metabolic/bariatric surgery (MBS) is the most cost-effective intervention for class II and III obesity, often demonstrating dominance (cost-saving) over non-surgical management.

For individuals with Class II or III obesity, metabolic/bariatric surgery is the most economically and clinically effective long-term solution, often paying for itself through reduced healthcare costs from comorbidity remission. It should be prioritized over pharmacotherapy for this group.

Increases in lean mass (hypertrophy) are not significantly associated with improvements in muscle strength, endurance, or power in resistance-trained young males, indicating that functional adaptations occur independently of muscle size gains.

If you are a trained individual, do not assume that your strength gains are limited by your muscle size. You can improve your strength, power, and endurance significantly without necessarily gaining large amounts of lean mass. Focus on technical proficiency and neural adaptation (e.g., heavy loads, specific power drills) rather than just volume for hypertrophy, as these functional improvements can occur independently of muscle growth.

Improvements in cardiorespiratory fitness (VO2peak) do not consistently correlate with improvements in Metabolic Syndrome risk factors (blood pressure, lipids, glucose) following exercise training.

Do not assume that an increase in your maximum oxygen uptake (VO2peak) means your blood pressure or cholesterol has automatically improved. This study shows these two improvements are not consistently linked. You must monitor your specific risk factors (blood pressure, lipids, glucose) separately to assess the metabolic benefit of your exercise routine.

Obesity pharmacotherapy is recommended against for compounded medications or unapproved medications due to safety and efficacy concerns.

Avoid compounded weight loss medications. They are not approved, may be unsafe, and are not proven to work. Stick to FDA/Health Canada-approved medications prescribed by your doctor.

Supplementation with long-chain omega-3 and omega-6 polyunsaturated fatty acids does not statistically significantly reduce the risk of coronary outcomes in randomized controlled trials.

Taking omega-3 supplements (0.3-6g/day) does not appear to significantly reduce the risk of coronary disease based on this large review of randomized trials. While some observational studies suggested benefits, the higher-quality trial data did not confirm a significant protective effect.

Grip strength is not significantly associated with prostate cancer mortality, although it is associated with the incidence of prostate cancer.

For men, low grip strength does not predict death from prostate cancer. However, it is associated with a higher *incidence* of prostate cancer, possibly because stronger men are more health-conscious and get screened more often. Do not use grip strength to rule out prostate cancer risk.

Adapting to a ketogenic low carbohydrate, high fat (LCHF) diet during intensified training impairs exercise economy and negates performance improvements in elite endurance athletes, despite increasing peak aerobic capacity.

For elite endurance athletes, switching to a strict ketogenic diet during intense training blocks is likely counterproductive. While it may increase your ability to burn fat, it appears to make your body less efficient at using oxygen at race speeds, leading to no performance gain despite improved aerobic capacity. Stick to high-carbohydrate or periodized carbohydrate strategies for performance outcomes.

Long sleep duration (>8 hours) in older adults is associated with increased mortality, but this risk is primarily explained by underlying health conditions and lifestyle factors rather than inflammation.

If you are an older adult sleeping more than 8 hours, your mortality risk is higher, but this is likely due to underlying health conditions or lifestyle factors rather than the sleep itself. Focus on managing chronic diseases and maintaining a healthy lifestyle rather than restricting sleep.

Initiation of modern antiretroviral therapy (ART), specifically integrase strand transfer inhibitors (INSTIs) like dolutegravir and bictegravir combined with tenofovir alafenamide (TAF), causes significant, sustained weight gain in people living with HIV, disproportionately affecting women and Black patients.

If you are living with HIV and starting or taking modern medication (specifically drugs ending in '-gravir' like dolutegravir or bictegravir, and TAF), expect significant weight gain, especially if you are a woman or Black. This is not just 'getting older' or 'eating too much'; it is a known side effect of the medication's interaction with your metabolism. Talk to your doctor about your risk factors. They may consider regimens with TDF (which mitigates weight gain) or other alternatives, though these may have other side effects. Be aware that standard diet and exercise might be less effective for this specific type of gain, and emerging weight-loss medications might be considered in the future.