Browse the evidence

Bariatric surgery (Roux-en-Y gastric bypass or sleeve gastrectomy) is technically feasible and safe for patients with pre-existing ileostomy or colostomy, without causing increased ostomy output or dehydration.

If you have an existing ostomy (ileostomy or colostomy) and are considering bariatric surgery, current preliminary evidence suggests it is feasible and safe, with no increased risk of dehydration or output changes compared to patients without an ostomy. Consult with a bariatric surgeon to evaluate your specific case, as individual factors like the cause of your ostomy and overall health status will determine your candidacy.

In the US, higher nutrition knowledge (better discernment of healthy vs. unhealthy foods) is positively associated with higher BMI.

Knowing what is healthy doesn't automatically lead to weight loss. This study found that in the US, people with higher nutrition knowledge had higher BMI, likely because knowledge alone doesn't overcome environmental or social barriers. Don't blame yourself for not losing weight despite knowing the facts. Focus on practical strategies to navigate your environment, not just on learning more about food.

In the US, higher food insecurity is inversely associated with BMI.

If you are experiencing food insecurity, you may find your weight is lower than expected. This study suggests that in the US, food insecurity is linked to lower BMI, likely due to limited access to food. If you are struggling to afford food, prioritize nutrient-dense, affordable options and seek community resources. Your health is important, and help is available.

Incretin-based therapies may attenuate intestinal iron absorption, independent of reduced intake, potentially contributing to iron deficiency in susceptible individuals.

Monitor iron levels if you have a history of anemia or low iron, as semaglutide may slightly reduce absorption.

Heterozygous variants in the POMC gene (specifically p.Arg90His, p.Ser94Gly, p.Ser94=, and p.Ala195=) are associated with an intermediate obesity phenotype in adults, likely due to haploinsufficiency affecting melanocortin peptide processing.

If you carry a heterozygous POMC variant, you may have an intermediate form of genetic obesity that responds differently to standard interventions. This information can help tailor your treatment plan, though functional validation of specific variants is still needed.

Tirzepatide as an adjunct to insulin in adults with Type 1 Diabetes and overweight/obesity produces significant body weight reduction and reduced insulin requirements, but current evidence is insufficient to establish durable glycaemic benefit or long-term safety.

For adults with Type 1 Diabetes and obesity, Tirzepatide is a promising tool for significant weight loss and reducing insulin needs. However, it is not yet proven to reliably improve long-term blood sugar control or safety. If used, it requires careful monitoring for side effects like nausea and potential risks like DKA, especially if insulin is reduced too aggressively. It is currently an investigational option, not a standard of care.

BPC-157 accelerates tissue repair (tendons, muscles, ligaments, GI mucosa) by stimulating angiogenesis and modulating inflammation, though it lacks FDA approval and robust human clinical trials.

BPC-157 is a peptide studied for its ability to speed up the healing of tendons, muscles, and gut lining. While animal studies show promising results for tissue repair, it is not yet approved by the FDA for human use. It is sometimes used off-label in sports medicine, but robust human clinical trials are still needed to confirm its safety and efficacy.

Carnivore and animal-based diets do not consistently improve athletic performance and may impair high-intensity exercise capacity due to reduced muscle glycogen and constrained metabolic flexibility.

Do not switch to a carnivore or animal-based diet expecting better performance, especially if your sport involves sprinting, lifting, or high-intensity intervals. These diets reduce muscle glycogen and make it harder to produce energy quickly. While you might lose weight or feel less bloated, your high-intensity performance will likely suffer. Stick to established sports nutrition guidelines that prioritize carbohydrate availability for intense training.

Carnivore and animal-based diets pose significant risks for micronutrient deficiencies, altered gut microbiota, and unfavorable lipid profiles, with no long-term safety data in athletes.

Be cautious with long-term carnivore or animal-based diets. You risk missing key nutrients like fiber, vitamin C, and magnesium, which can affect gut health and recovery. Your cholesterol levels might also rise significantly. There is no long-term safety data for athletes on these diets. If you choose to try it, monitor your blood work closely and consider it experimental, not optimal.

Exercise training has no significant effect on weight maintenance (prevention of weight regain) after an initial weight loss phase.

Exercise alone is not enough to keep weight off after you've lost it. To maintain your weight loss, you need to focus on sustainable dietary changes, as exercise has not been shown to prevent weight regain on its own.

Ramadan Fasting (RF) protocols (28-30 days) have insufficient evidence to draw definitive conclusions regarding their effects on body weight, composition, or glycemic control compared to Time-Restricted Feeding.

Do not rely on Ramadan Fasting as a proven, standalone strategy for weight loss or metabolic health improvement based on current scientific evidence. The data is too sparse to recommend it over established methods like TRF.

The renal safety of long-term low-carbohydrate diets in obese individuals remains undetermined due to insufficient reporting of renal function data in clinical trials.

Do not start a low-carb diet if you have existing kidney disease. For healthy obese individuals, current data does not show harm, but long-term safety is not proven because most studies don't track kidney function. Monitor your health with a doctor.

The impact of a ketogenic diet on endurance performance is controversial and context-dependent, with some studies showing improvement and others showing impairment.

If you are an endurance athlete, switching to keto is risky for performance. Some people improve, but many see a drop in high-intensity performance. It requires a long adaptation period and may not be suitable for all types of endurance sports.

Intermittent fasting does not significantly improve cardiovascular risk factors (lipid profile, blood pressure) or diabetes markers (HbA1c, fasting glucose) compared to daily caloric restriction.

Do not expect intermittent fasting to fix your cholesterol or blood sugar better than a standard calorie-restricted diet. The primary benefit is weight loss, which may indirectly help these markers, but the fasting pattern itself offers no superior advantage for cardiovascular or diabetes risk factors.

Menstrual cycle phase has a trivial effect on exercise performance in eumenorrheic women, with no evidence supporting general guidelines for modulating training across phases.

Stop tracking your menstrual cycle to schedule workouts. The science shows that performance differences across phases are trivial and inconsistent. Instead of trying to align your training with your hormones, focus on consistent training habits. If you notice a personal pattern where you feel weaker or stronger in a specific phase, adjust your expectations for that specific session, but do not change your overall training plan based on the calendar.

SGLT-2 inhibitors increase the risk of genital infections, while GLP-1 receptor agonists may increase the risk of severe gastrointestinal events.

Be aware of potential side effects: SGLT-2 inhibitors can increase genital yeast infections, and GLP-1 agonists can cause nausea or GI issues. These are common and manageable, but you should discuss prevention strategies (like hygiene for SGLT-2 or slow dose titration for GLP-1) with your doctor before starting.

Vitamin D supplementation may reduce the severity and risk of COVID-19 infection, particularly in individuals with vitamin D deficiency, by modulating immune response and reducing pro-inflammatory cytokines.

Consider Vitamin D supplementation, especially if you have limited sun exposure or are elderly. Aim for a daily intake of up to 2000 IU, and ensure adequate magnesium intake to support Vitamin D metabolism. Consult a healthcare provider for personalized advice.

Computer and Internet use may be favorably associated with cognitive function in older adults.

For older adults, using computers and the Internet may support cognitive function, unlike passive TV viewing. Engaging with technology can be a beneficial sedentary activity.

Moderate consumption of red wine (and beer) is associated with a lower prevalence of metabolic syndrome compared to abstainers or heavy drinkers, whereas liquor/spirit intake increases risk.

If you drink alcohol, moderate wine consumption (up to 1 drink/day for women, 2 for men) is associated with better metabolic health than abstaining or drinking spirits. Do not start drinking if you don't already.

Smoking increases the risk of metabolic syndrome, and smoking cessation is associated with an increased risk of MetS in the short-to-medium term (up to 10 years) due to weight gain and metabolic changes.

Quit smoking to prevent metabolic syndrome. Be aware that you may gain weight and have a higher MetS risk for up to 10 years after quitting. Counter this by adopting a calorie-restricted diet and increasing physical activity immediately.

Selenium status has a complex, non-linear relationship with diabetes risk, where both deficiency and excess (high serum levels) may be associated with adverse metabolic outcomes depending on geographic and baseline status.

Do not supplement with selenium unless you live in a selenium-deficient area or have a confirmed deficiency. High selenium levels may actually increase diabetes risk. Focus on getting selenium from a varied diet, and consult a doctor for testing if you are considering supplementation.

Natural plant-derived antioxidants (polyphenols, carotenoids, etc.) may mitigate obesity and metabolic complications by reducing intracellular oxidative stress, scavenging reactive oxygen species (ROS), and preventing NF-κB activation.

Focus on consuming a diet rich in plant-based antioxidants (polyphenols, flavonoids, carotenoids) as part of a broader lifestyle strategy. While these compounds show promise in reducing oxidative stress and inflammation linked to obesity, they are not a standalone cure. Prioritize lifestyle modifications like diet changes and reduced sedentarism, using plant-derived foods as a supportive component rather than a primary intervention.

Lifestyle interventions may improve the Free Androgen Index (FAI) in women with PCOS, but evidence quality is low.

Lifestyle changes may help lower male hormone levels (FAI) in women with PCOS. However, the evidence is not strong enough to be certain, so this should be viewed as a potential benefit rather than a guaranteed outcome.

Faecal Microbiota Transplantation (FMT) from lean donors shows promise for improving insulin sensitivity in metabolic syndrome, but current human evidence is limited, small, and unreplicated.

FMT from lean donors may improve insulin sensitivity, but it is not yet a standard or proven treatment for diabetes due to limited and unreplicated human data. Do not pursue this outside of clinical trials.