Browse the evidence

In non-diabetic patients, a ketogenic diet increases LDL cholesterol and total cholesterol compared to low-fat diets, whereas in diabetic patients, it improves lipid profiles by lowering triglycerides and raising HDL.

If you are non-diabetic and overweight, be aware that a ketogenic diet may raise your LDL and total cholesterol compared to a low-fat diet. If you have diabetes, a ketogenic diet tends to improve your triglycerides and HDL (good cholesterol). Monitor your lipids closely if you choose this diet.

Supplementing a very low calorie diet (VLCD) with long-chain n-3 polyunsaturated fatty acids (n-3 PUFA) significantly enhances weight loss and BMI reduction in severely obese women compared to VLCD alone.

If you are following a strict, low-calorie diet for obesity, adding a high-quality fish oil supplement (providing roughly 2.8g of EPA/DHA daily) may help you lose weight and body fat faster than dieting alone. This works by boosting your body's fat-burning (ketosis) and reducing fat storage signals.

n-3 PUFA supplementation during caloric restriction increases ketogenesis (beta-hydroxybutyrate levels) and reduces lipogenesis (palmitoleic acid levels), indicating enhanced fatty acid oxidation.

n-3 PUFAs may help your body burn fat more efficiently during a diet by increasing ketone production and reducing the creation of new fat.

Increased serum levels of Docosahexaenoic acid (DHA) are significantly correlated with greater BMI loss during n-3 PUFA supplementation.

Not all n-3 supplements work equally for everyone; those who see the biggest weight loss benefits tend to have higher levels of DHA in their blood.

A biphasic ketogenic Mediterranean diet (KEMEPHY) protocol, alternating short ketogenic phases with longer maintenance phases, enables significant long-term weight loss and maintenance in obese subjects without the typical weight regain seen in standard diets.

To lose weight long-term, try alternating short periods (20 days) of very low-carb eating with longer periods (months) of a balanced Mediterranean diet. Use protein-rich meal replacements and herbal supplements during the low-carb phases to manage hunger and fatigue. This approach helps you lose weight and keep it off by preventing the metabolic and hormonal backlash that often causes weight regain when you return to normal eating.

Time-restricted feeding (16:8 protocol) for 3 months significantly reduces body weight, BMI, and waist circumference in obese women, but does not significantly alter blood biomarkers associated with metabolic syndrome (glucose, lipids, insulin).

If you are obese and sedentary, trying a 16:8 fasting window (e.g., 8 PM to 12 PM) for 3 months will likely help you lose about 4 kg and reduce your waist size. However, do not expect your blood sugar or cholesterol numbers to improve significantly just from the timing; the benefit comes from the resulting weight loss. This approach is easier to stick to than strict calorie counting because you can eat normal foods during your 8-hour window.

Reduction in 30-year cardiovascular disease risk (CVDRisk30y) is significantly correlated with changes in body fat percentage (%BF) and skeletal muscle percentage (%MM) following TRF, even without changes in traditional blood biomarkers.

Focus on losing body fat and maintaining muscle mass through your TRF protocol, as these changes are the primary drivers for lowering your long-term cardiovascular risk score. Traditional blood tests may not reflect these improvements, so tracking body composition is a more useful metric for this specific intervention.

Ramadan intermittent fasting leads to significant reductions in body weight and fat-free mass across all adult demographics, with fat loss occurring primarily in males and younger subjects (<35 years).

If you practice Ramadan fasting, expect to lose weight and some lean mass. Men and younger individuals are more likely to lose fat, while older women may see less fat loss. To minimize muscle loss, prioritize protein intake during non-fasting hours and consider resistance training.

A 45-day VLCKD significantly improves metabolic parameters (weight, BMI, blood pressure, lipids, insulin resistance) regardless of protein source, but animal protein may negatively impact renal markers.

A strict 780-calorie ketogenic diet for 45 days will significantly improve your weight, blood pressure, and blood sugar/insulin levels, regardless of whether you use whey, vegetable, or animal protein. However, if you have kidney concerns, be cautious with animal protein sources as they may slightly worsen renal markers in this context.

Intermittent Energy Restriction (IER) produces weight loss outcomes equivalent to Continuous Energy Restriction (CER) over long-term interventions (≥6 months), with no statistically significant difference in mean weight loss between the two methods.

If you are struggling with the daily rigidity of continuous calorie restriction, try an Intermittent Energy Restriction (IER) approach like the 5:2 diet or Alternate Day Fasting. The evidence shows you will lose the same amount of weight as if you restricted calories every day, but with more flexibility. Focus on consistency over the long term (6+ months) and seek behavioral support to manage the inevitable weight loss plateau that occurs around 6 months.

A 6-month vegan low-carbohydrate diet (26% carbohydrate, 43% fat, 31% protein) produces greater LDL-C reduction and modestly greater weight loss compared to a high-carbohydrate lacto-ovo vegetarian diet in hyperlipidaemic adults.

To lower LDL-C and lose weight, try a vegan low-carb diet focusing on soy, gluten (seitan), nuts, and vegetable oils while restricting carbohydrates to about 26% of your calories. Ensure you are in a caloric deficit (approx. 60% of estimated needs) and prioritize these specific plant-based macronutrients over animal products or high-starch vegetables.

A combined weight loss intervention using meal replacements and guided aerobic exercise produces comparable total weight loss in pre- and postmenopausal women, but postmenopausal women experience superior metabolic risk factor improvements and preserve lean body mass more effectively.

For postmenopausal women, a structured weight loss program using meal replacements and supervised aerobic exercise is highly effective. While total weight loss may be similar to younger women, the metabolic benefits (blood pressure, cholesterol, glucose) are often greater, and muscle mass is better preserved. Focus on high-protein meal replacements and consistent aerobic activity to maximize these benefits.

Obese individuals with a 'thrifty' phenotype, characterized by a large decrease in 24-hour energy expenditure during fasting and a small increase during overfeeding, lose significantly less weight during caloric restriction than those with a 'spendthrift' phenotype.

If you are struggling to lose weight despite strict adherence to a calorie deficit, your body may have a 'thrifty' metabolic phenotype that aggressively reduces energy expenditure. This is a biological reality, not a personal failure. Understanding this can help manage expectations and prevent discouragement, as standard caloric deficits may yield smaller results for you than for others.

For overweight breast cancer survivors, both low-fat and reduced-carbohydrate diets produce equivalent significant weight loss and metabolic improvements when energy intake is restricted, indicating that caloric deficit drives outcomes more than macronutrient composition.

If you are a breast cancer survivor looking to lose weight, you do not need to choose between low-fat and low-carb diets based on ideology. Both work equally well for weight loss and metabolic health as long as you create a consistent calorie deficit (approx. 500 kcal/day) and adhere to professional counseling. Focus on sustainable energy restriction rather than restricting specific macronutrients to extremes.

Reduced carbohydrate diets specifically lower triglycerides, whereas low-fat diets do not significantly reduce triglycerides despite similar weight loss.

If you have high triglycerides, a reduced-carbohydrate diet may offer a specific metabolic advantage over a low-fat diet, even if your weight loss is the same. This can improve your cardiovascular risk profile.

Weight loss via calorie restriction alone, without resistance training, leads to a loss of appendicular lean mass and an increased prevalence of sarcopenia in breast cancer survivors.

If you lose weight through diet alone, you risk losing muscle mass, which can lead to sarcopenia. To preserve muscle, combine calorie restriction with resistance training.

Adherence to the PSMF duration is strongly correlated with the magnitude of weight loss.

Your results are directly tied to how long you stick to the diet plan. The study shows that patients who stayed on the PSMF longer lost more weight.

Males with severe obesity experience significantly greater excess body weight loss and greater reduction in gamma-glutamyl transferase (a marker for NAFLD) compared to females following a 25-day very low-carbohydrate ketogenic diet (VLCKD).

If you are female, you may lose less weight and see less improvement in liver health markers than a male following the exact same very low-carb ketogenic diet protocol. This is likely due to differences in body fat distribution and hormones. Do not assume your results will match male benchmarks; focus on consistency and consult a professional to adjust expectations.

The sex-based difference in VLCKD efficacy is attenuated in post-menopausal females, who experience benefits more similar to males than pre-menopausal females.

If you are post-menopausal, your body's response to a very low-carb ketogenic diet may be more similar to a man's than to a pre-menopausal woman's. This is likely due to hormonal shifts. You may see better results than expected if you adjust your strategy to account for these changes rather than assuming you can't lose weight.

Increasing eating frequency (grazing) during a behavioral weight loss intervention significantly reduces self-reported hunger compared to limiting intake to three meals, but does not result in greater reductions in energy intake or BMI.

If you are trying to lose weight, eating more frequently (grazing) might help you feel less hungry, but it won't necessarily help you lose more weight than eating three structured meals. Since both approaches resulted in similar weight loss and energy intake, choose the pattern that you can stick to consistently without feeling deprived or overwhelmed by constant eating.

Green coffee bean extract (GCA) containing high chlorogenic acid significantly reduces body weight, BMI, and percent body fat in overweight adults without requiring changes to diet or exercise.

If you are overweight, taking green coffee bean extract (specifically high-chlorogenic acid extracts like GCA) may help you lose weight and reduce body fat, even if you don't change your diet or exercise habits. The study used doses between 700mg and 1050mg per day. However, note that this specific study has been retracted, so verify current scientific consensus before starting.

Intermittent energy restriction (IER) using a 'week-on, week-off' strategy produces weight loss and weight loss maintenance comparable to continuous energy restriction (CER) over 12 months.

If you find daily calorie counting unsustainable, try a 'week-on, week-off' approach. Eat your normal diet for one week, then restrict calories (e.g., to ~1300 kcal) for the next week. Repeat this cycle for a year. This study shows you can achieve the same weight loss and maintenance as eating restricted calories every day, which may help you stick with it longer.

Continuous energy restriction (CER) leads to greater improvements in diet quality (Healthy Eating Index) compared to intermittent energy restriction (IER) over 12 months.

If your goal is not just weight loss but also improving your overall diet quality (e.g., eating more fruits, vegetables, and less saturated fat), continuous daily restriction may be more effective than intermittent restriction. However, if your main goal is simply weight loss and maintenance, intermittent restriction is equally effective for that specific outcome.

Short-term weekly intermittent energy restriction (IER) produces weight loss equivalent to continuous energy restriction (CER) in adults with overweight or obesity, making it a viable alternative treatment option.

If you struggle with daily calorie counting, try a weekly intermittent energy restriction plan where you restrict calories (420-1500 kcal) for 2-3 days a week (or in 7-day cycles) and eat normally otherwise. This approach yields the same weight loss as daily restriction over 3-6 months. However, be aware that long-term maintenance is not guaranteed by the diet alone; you likely need active weight maintenance strategies after the intervention ends.