Browse the evidence

While IER+MED reduces visceral adipose tissue (VAT) more than DASH, this advantage disappears when adjusting for total fat mass loss, suggesting the VAT reduction is proportional to overall weight loss rather than specific to visceral fat mobilization.

Don't expect intermittent fasting to melt belly fat faster than other diets if you lose the same amount of total weight. The VAT reduction you see is largely due to overall fat loss. Focus on the total fat loss and the sustainability of the diet pattern.

IER+MED improves liver function (measured by Alanine Transaminase/ALT) more effectively than a DASH diet, independent of total fat mass loss.

If you have elevated liver enzymes, switching to an IER+MED pattern may offer specific liver health benefits beyond what you get from just eating a healthy diet (DASH).

Men experience significantly greater long-term weight loss from VLED+BT compared to women, while women show less difference between VLED+BT and BT alone.

Men tend to lose significantly more weight long-term with VLED+BT than women do. Women still benefit, but the difference between using VLED and not using it is smaller. This suggests that treatment plans might need to be tailored differently for men and women to achieve optimal results.

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.

Resistance training alone significantly increases lean mass in overweight/obese premenopausal women, even without a prescribed caloric deficit.

If your goal is to build muscle or improve your shape without losing weight, resistance training is effective even if you don't change your diet. Focus on progressive overload with compound exercises. However, be aware that without a caloric deficit, you will not lose fat, so your weight might stay the same or increase slightly due to muscle gain.

Intermittent energy restriction (IER) reduces body weight and fat mass compared to a usual diet, with effects on weight loss being similar to continuous energy restriction (CER).

If you struggle with daily calorie counting, try Intermittent Energy Restriction (IER). This involves restricting calories to 20-25% of your normal intake (or fasting completely) on 1-2 days per week (like the 5:2 diet) or every other day (ADF), while eating normally on other days. This approach reduces body weight and fat mass just as effectively as continuous daily restriction, offering more flexibility.

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.

Post-starvation refeeding with a restricted diet (800 cal) leads to rapid reaccumulation of lean tissue (water and protein) while continuing to lose fat, resulting in a net fat loss rate higher than during the starvation phase itself.

After a period of fasting, do not binge. Return to a moderate calorie deficit (e.g., 800 calories). This study shows that your body will rapidly restore water and muscle mass while burning fat at a rate higher than during the fast itself. The 'rebound' is actually a fat-burning advantage if you maintain the deficit.

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.

Tailoring the delivery style of weight loss interventions to male preferences (e.g., sports contexts, humor, direct language) improves engagement and effectiveness.

When designing or choosing a weight loss program, look for one that speaks your language. Men often respond better to direct, factual information and interventions that leverage existing interests, such as sports. Group settings that foster camaraderie and use humor appropriately can make the process more engaging and sustainable.

Interventions lasting less than 13 weeks may be at least as effective for weight loss as those lasting 13-26 weeks, potentially due to higher retention rates.

For busy individuals, a very short program (under 3 months) might be just as effective for weight loss as a 3-6 month program, possibly because it's easier to stick with. Consider shorter, intensive options if long-term commitment is a barrier.

Significant weight loss (approx. 24%) achieved via a very low calorie diet (550 kcal/day) significantly improves circulating levels of adiponectin and leptin, whereas a low carbohydrate/high protein diet yielding minimal weight loss does not.

To improve your adiponectin and leptin levels, focus on achieving significant weight loss. This study shows that a very low-calorie diet (around 550 kcal/day) combined with behavioral support led to substantial weight loss (~24%) and significant improvements in these hormones. A low-carb diet that does not result in weight loss did not produce these benefits, suggesting that the weight loss itself is the primary driver of metabolic improvement, not the specific macronutrient ratio.

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.

Waist circumference is a valid, pragmatic anthropometric marker for estimating changes in visceral adipose tissue (VAT), though it explains only modest variance (25-75%) due to subcutaneous fat variability.

Use waist circumference as a practical, accessible way to track your visceral fat loss progress. It is the best non-invasive marker available. While it is not as precise as an MRI scan, a reduction in waist circumference (especially >2 cm) is a strong indicator of reduced visceral fat. Measure it consistently to monitor your lifestyle interventions.

Fat loss magnitude is determined exclusively by the size of the energy deficit, regardless of whether that deficit is created through dietary restriction alone or a combination of diet and aerobic exercise.

To lose fat, you must create a caloric deficit. Whether you achieve this deficit by eating less, moving more, or a combination of both, the amount of fat you lose will be determined by the size of that deficit, not the method used. If you match the deficit, diet-only and diet-plus-exercise yield equivalent fat loss, though exercise improves fitness.

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.

Adherence to Time-Restricted Feeding (TRF) is generally high and well-tolerated, with compliance rates of 65-75% in short-term studies, and greater fasting duration is associated with higher adherence.

If you are worried about sticking to a diet, TRF is a good option. Most people find it easy to follow, with about 7 out of 10 people sticking to it for several months. Interestingly, people who fast for longer periods (e.g., 12 hours) often stick with it better than those who fast for shorter periods.

A high-protein diet during energy restriction activates mitochondrial oxidation, which is positively correlated with resting energy expenditure and inversely related to fat mass, potentially explaining the enhanced weight loss.

High-protein diets may work by boosting your mitochondria's ability to burn fuel, which helps maintain your metabolic rate and burn more fat, even when you are eating fewer calories.

Low-carbohydrate diets improve long-term cardiovascular risk factors (specifically triglycerides and HDL cholesterol) compared to balanced diets, despite no long-term difference in weight loss.

Even if your weight stabilizes to match a balanced diet after a year, your blood lipid profile may improve on a low-carb diet. Specifically, expect lower triglycerides and higher HDL ('good') cholesterol, which are positive markers for heart health.

Large initial weight loss achieved via a Very Low Calorie Diet (VLCD) combined with behavioral therapy and group support predicts significant long-term weight loss maintenance (1-3 years), refuting the belief that rapid weight loss leads to poorer long-term outcomes.

If you are obese and motivated, a medically supervised Very Low Calorie Diet (under 800 kcal/day) combined with weekly group support and behavioral therapy can lead to significant, lasting weight loss. The key is not how fast you lose, but that you stay engaged with the support program after the diet phase. Large initial losses predict better long-term maintenance.

Baseline intestinal microbiome composition predicts the magnitude of weight loss and improvement in hepatic steatosis in response to a calorie-restricted diet, independent of dietary compliance.

If you are struggling to lose weight on a standard calorie-restricted diet despite good adherence, your gut microbiome might be resisting the change. This is not a personal failure. Future testing may identify if your specific microbial profile (e.g., high levels of Escherichia/Shigella or Klebsiella) predicts poor response to simple calorie restriction, potentially guiding you toward other interventions like bariatric surgery or targeted microbiome modulation.

A nutritionally balanced, moderately energy-restricted diet (55% carb, 30% fat, 15% protein) induces a metabolic shift in obese women from carbohydrate oxidation to lipid oxidation over a 10-week period.

For obese women, a 10-week diet providing 55% carbs, 30% fat, and 15% protein, set 500 calories below maintenance, successfully shifts the body's fuel preference from burning sugar to burning fat. This shift occurs alongside a modest but significant weight loss of about 4.3 kg, suggesting that balanced moderate restriction is an effective strategy for improving metabolic flexibility without extreme hunger.

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.