Browse the evidence

Intermittent energy restriction (IER) improves insulin sensitivity (reduces fasting insulin and HOMA-IR) in non-diabetic populations compared to continuous energy restriction (CER).

For non-diabetic individuals, IER may offer metabolic benefits beyond weight loss, specifically improving insulin sensitivity. This is achieved by lowering fasting insulin levels. If you have diabetes, consult a doctor to adjust medications before starting IER to prevent hypoglycemia.

Intermittent energy restriction (IER) improves intermediate disease markers, specifically triacylglycerols and systolic blood pressure, compared to a usual diet, but has no effect on LDL-cholesterol, fasting glucose, or HbA1c.

Beyond weight loss, IER can improve blood pressure and triglyceride levels. However, it does not significantly affect LDL cholesterol, fasting glucose, or HbA1c compared to a usual diet. If you have diabetes, consult a doctor as some studies reported hypoglycemia.

Alternate day fasting with a low-carbohydrate diet significantly reduces LDL cholesterol, systolic blood pressure, and fasting insulin in adults with obesity.

If you have high LDL, high blood pressure, or high fasting insulin, this specific combination of fasting and low-carb eating may help improve these markers. Monitor your levels with your doctor, as individual responses to low-carb diets on cholesterol can vary.

Early Time-Restricted Eating (eTRE) combined with calorie restriction is more effective for weight loss and fat mass reduction than delayed TRE (dTRE) or broader TRE windows.

If you can manage it, shifting your eating window to earlier in the day (eTRE) combined with a calorie deficit yields better weight and fat loss results than shifting it to later in the day (dTRE). However, if early eating is socially unsustainable, any consistent TRE window with a calorie deficit is still superior to no TRE.

Consuming the majority of daily carbohydrates at dinner, while maintaining a standard low-calorie diet, results in greater weight loss, improved satiety, and better metabolic markers compared to distributing carbohydrates evenly throughout the day.

If you are trying to lose weight, try moving most of your carbohydrates (rice, pasta, bread, fruit) to your evening meal. Keep your total calories and protein/fat intake the same as you would normally. This simple shift may help you feel less hungry during the day and lose slightly more weight than if you spread those carbs out evenly.

Intermittent fasting during Ramadan significantly improves insulin sensitivity and reduces insulin resistance in healthy young men, independent of changes in fasting plasma glucose.

For healthy young men, observing Ramadan-style intermittent fasting (sunrise to sunset) for about a month can improve how your body handles insulin, even if your fasting blood sugar numbers don't change. This benefit comes from reduced insulin levels and weight loss, provided you maintain your usual activity level.

Intermittent fasting during Ramadan significantly reduces serum leptin levels in healthy young men, correlating with weight loss, while adiponectin levels remain largely unchanged.

Fasting for a month lowers your leptin levels, a hormone that signals energy stores to your brain. This drop correlates with your weight loss. Adiponectin, another metabolic hormone, stays relatively stable. This hormonal shift is part of the body's adaptation to reduced energy intake.

Early Time-Restricted Eating (eTRE) with an 8-hour window starting before noon significantly reduces body weight and fat mass while improving glycemic markers (fasting glucose, insulin, HOMA-IR) and triglycerides in young adults with delayed sleep-wake cycles, whereas late TRE (starting after noon) fails to produce these metabolic benefits.

If you are a young adult with a late sleep schedule, try shifting your eating window to start before noon (e.g., 8am-4pm or 9am-5pm) for 4 weeks. Ensure you get about 20g of extra protein daily (via snacks or shakes) to protect muscle. This specific timing appears necessary to reduce fat and improve blood sugar control; starting your window after noon may not yield these metabolic benefits.

A time-restricted eating protocol with a 16-hour fasting window (16:8) significantly reduces body mass and absolute fat mass in metabolically healthy, non-trained individuals, whereas 12-hour and 14-hour fasting windows do not produce significant changes.

If you are healthy and not trying to build muscle, try eating all your meals within an 8-hour window (e.g., 10am to 6pm) and fasting for the other 16 hours daily for 8 weeks. Do not try to restrict calories; just stick to the timing. You may lose fat mass without changing how much you eat, but 12-hour or 14-hour windows likely won't work for you.

Time-restricted eating (TRE) significantly improves cardiometabolic risk factors, specifically reducing insulin, total cholesterol, and LDL concentrations.

Focus on aligning your eating window with your circadian rhythm (e.g., 16:8). This may improve insulin sensitivity and lipid profiles independently of major weight loss, particularly if you have metabolic risk factors.

Combining continuous energy restriction (CER) with 16/8 time-restricted feeding (TRF) yields equivalent weight and fat loss to CER alone, but superior preservation of fat-free mass and skeletal muscle.

If you are trying to lose weight while keeping your muscle, adding an 8-hour eating window (like 12pm-8pm) to your calorie deficit won't make you lose fat faster than just eating fewer calories. However, it may help you keep more muscle mass. Focus on hitting your protein and calorie targets; the timing is a tool for adherence or muscle sparing, not a magic fat-loss multiplier.

CER alone increases cortisol levels, whereas CER combined with 16/8 TRF does not, suggesting TRF may mitigate the stress response to caloric restriction.

Caloric restriction can raise stress hormones like cortisol, which might hinder muscle retention. If you are doing a diet, adding an eating window might help keep these stress hormones lower than if you just restrict calories without timing constraints.

Lactobacillus sp. supplementation significantly decreases leptin levels and increases adiponectin levels in non-comorbid obese individuals.

Lactobacillus supplementation may help improve your hormonal profile by lowering leptin (which can promote fat storage) and raising adiponectin (which improves insulin sensitivity and fat burning). This hormonal shift supports weight management efforts.

Ketogenic diets are effective for fat mass reduction but are less effective than carbohydrate-rich diets for muscle mass gain, potentially due to reduced testosterone and IGF-1 levels.

If your main goal is to build muscle, avoid ketogenic diets as they may hinder growth. If your goal is fat loss, keto works, but monitor your strength training performance.

Increasing the regularity of meal times (reducing mealtime variability) leads to significant weight loss without requiring calorie restriction or changes in macronutrient composition.

Use a smartphone app to track your meals for two weeks to identify your most frequent eating times. Then, create a personalized schedule that restricts your meals to those specific times for six weeks. Do not worry about changing what or how much you eat; focus only on making your meal times consistent and regular. This approach led to an average weight loss of 2.6 kg in the study without calorie counting.

Personalizing meal schedules to an individual's chronotype (specifically aligning meal times with their mid-sleep phase) enhances weight loss effectiveness compared to generic regularity.

If you have a flexible schedule, try to align your main meals with your natural sleep rhythm. If you are a 'night owl', your optimal eating window might be later than the standard 9-5 worker's. The study suggests that correcting large discrepancies between your workday and weekend eating times (meal jet lag) can boost weight loss.

Intermittent fasting (IF) produces weight loss comparable to continuous calorie restriction while offering superior improvements in insulin sensitivity and lipid profiles through a metabolic switch to ketone-based energy.

Intermittent fasting is a viable weight loss strategy that works as well as traditional calorie counting but may offer better metabolic benefits like improved insulin sensitivity. You can choose from several methods: eating normally on 2 days and restricting calories on 2 others (5:2), alternating between fasting and eating days (ADF), or limiting your daily eating to an 8-hour window (16:8). The key is consistency and allowing your body to switch from burning glucose to burning fat (ketones). Start with a protocol that fits your lifestyle, such as 16:8, and adjust based on your hunger and energy levels.

A lower omega-6 to omega-3 ratio (2-3:1) suppresses inflammation in patients with rheumatoid arthritis, and a ratio of 5:1 has a beneficial effect on asthma, whereas a ratio of 10:1 has adverse consequences.

If you have rheumatoid arthritis, aim for a very low omega-6 to omega-3 ratio of 2-3:1. If you have asthma, a ratio of 5:1 may be beneficial. This involves reducing omega-6 oils and increasing omega-3 sources. The optimal ratio depends on your specific health condition.

Vitamin D deficiency (serum 25-OH D ≤15 ng/mL) is associated with a significantly increased risk of incident cardiovascular disease, with this association being particularly strong and statistically significant in individuals with hypertension.

If you have high blood pressure, getting your vitamin D levels checked is a prudent step. This study found that low levels (≤15 ng/mL) were linked to a significantly higher risk of heart events in hypertensive individuals. While fixing low levels doesn't guarantee prevention, it may be a valuable part of managing your overall cardiovascular risk, especially given the safety and low cost of supplementation.

Probiotics improve lipid profiles, reduce blood pressure, and lower glucose levels in patients with metabolic disorders (obesity, type 2 diabetes, insulin resistance).

If you have high cholesterol or blood sugar, adding specific probiotics to your diet may offer modest improvements in lipid profiles and glucose control. However, these effects are smaller than those of prescription drugs, so do not stop your medications without consulting your doctor.

Short sleep duration is consistently associated with a significantly increased risk of obesity in both children and adults, with pooled odds ratios of 1.89 for children and 1.55 for adults.

Ensure you are getting sufficient sleep, as short sleep duration is linked to a higher risk of obesity. For adults, this often means aiming for more than 5-6 hours, and for children, more than 10 hours, though individual needs vary. While this study shows association, not causation, optimizing sleep is a low-risk, high-reward strategy for weight management.

High-intensity or intense aerobic exercise can cause transient hyperglycemia in individuals with Type 2 Diabetes, while moderate exercise generally lowers blood glucose.

Moderate aerobic exercise is generally recommended for lowering blood glucose. If you engage in brief, intense exercise, be aware that it may cause a temporary spike in blood glucose due to stress hormones. Monitor your levels if you are unsure how your body responds to high-intensity efforts.

Regular monitoring of cardiovascular risk factors (weight, BMI, waist circumference, blood pressure, lipids, glucose) is recommended for all women with PCOS, regardless of age, due to increased prevalence of risk factors.

Get your blood pressure, cholesterol, and blood sugar checked regularly, even if you feel healthy. PCOS increases your risk for heart issues, so monitoring these numbers annually or as advised by your doctor is crucial for long-term health.

Testosterone replacement therapy increases muscle mass and strength in hypogonadal and elderly men, but its efficacy in elderly women is less clear and requires further research.

Testosterone therapy can help increase muscle mass and strength in men with low testosterone, but it is not a one-size-fits-all solution. Women should be cautious as the benefits are less clear. Always consult a doctor before considering hormone therapy.