The 10 Best Diets for Weight Loss in 2026, Ranked by Evidence

Key takeaways

• Across 121 trials of 14 named diets, weight loss shrank for every diet by 12 months; only the Mediterranean diet kept its heart-risk benefits.^[1]
• In DIETFITS, healthy low-fat and healthy low-carb diets lost 5.3 and 6.0 kg at 12 months, a difference that was not significant.^[2]
• In PREDIMED, a Mediterranean diet with olive oil or nuts lowered major cardiovascular events by about 30% compared with a reduced-fat diet.^[5]
• Programs that include meal replacements led to 1.44 kg more weight loss at one year than other diets, and more with added support.^[6]
• Only alternate-day fasting beat daily calorie restriction in a 99-trial analysis, by 1.29 kg, mainly in shorter trials.^[10]

In short: Most well-designed weight-loss diets lose about the same amount of weight after a year, so the “best” diet is the one you can keep. Ranked by the evidence at 12 months or longer, the Mediterranean diet comes first (good long-term weight results plus fewer heart attacks and strokes in a large trial), followed by a reduced-calorie diet with any macro mix (two years of data) and a healthy low-carb plan. Pick the one that fits your food, budget and health needs.

This list ranks eating patterns, not branded products, and nothing here is for sale. It is general education, not personal medical or nutrition advice: if you have diabetes, kidney disease, a history of disordered eating, take medicines that affect blood sugar or blood pressure, or are pregnant, plan changes with your clinician or a registered dietitian. Each diet below also has its own full guide in our diets hub.

What the research says before we rank anything

The largest comparison of named diets is a 2020 network meta-analysis in the BMJ. It pooled 121 randomized trials with 21,942 adults and 14 popular diets. At six months, low-carb and low-fat patterns produced similar weight loss compared with usual eating (about 4.6 and 4.4 kg, or roughly 10 pounds), and most diets improved blood pressure. By 12 months, weight loss had shrunk for every diet, and the heart-risk benefits had largely faded for all of them except the Mediterranean diet.

Head-to-head trials say the same thing. In the POUNDS LOST trial (811 adults, two years), four reduced-calorie diets with very different fat, protein and carbohydrate levels all produced similar weight loss, about 4 kg (9 pounds) on average among completers, and attending the group sessions mattered more than the macro mix. In the Stanford DIETFITS trial (609 adults, 12 months), a healthy low-fat diet and a healthy low-carb diet differed by less than a kilogram. So we rank on long-term evidence first, then health markers, how easy each plan is to stick with, nutrient adequacy and cost, exactly as our How we choose method describes.

11.7 lbHealthy low-fat

13.2 lbHealthy low-carb

DIETFITS: average weight loss at 12 months

Item	Value
Healthy low-fat	11.7 lb
Healthy low-carb	13.2 lb

Reported as 5.3 kg and 6.0 kg; the difference was not statistically significant. Converted to pounds (1 kg = 2.2 lb).

Source: Gardner CD et al., JAMA 2018 (DIETFITS randomized trial, 609 adults) (checked on October 6, 2026)

The 10 best diets for weight loss, ranked

Each card names who the diet suits, three evidence points, what it costs and one honest drawback. “Price” here means the cost to follow it: none of these diets requires a paid program.

The 10 best diets for weight loss, ranked by evidence

1. 1

   1. Mediterranean diet

   Best for Long-term weight loss with heart benefits

   • 2-year trial: 4.4 kg (9.7 lb) average loss
   • PREDIMED: about 30% fewer major heart events vs a reduced-fat diet
   • only diet whose heart-risk benefits lasted at 12 months in the BMJ 2020 analysis

   Maker-stated specs

   Price No fee; ordinary groceries (olive oil, nuts and fish can raise the bill) (checked Oct 6, 2026)

   Drawback Calorie-dense foods such as olive oil and nuts still need portion limits for weight loss

2. 2

   2. Reduced-calorie diet, any macro mix

   Best for People who want flexibility and to eat foods they already like

   • POUNDS LOST: 811 adults, 2 years, similar loss with 35% to 65% carbohydrate
   • about 4 kg (9 lb) average loss in completers
   • 14% to 15% lost at least 10% of body weight

   Maker-stated specs

   Price No fee; ordinary groceries (checked Oct 6, 2026)

   Drawback Counting or estimating calories takes effort, and weight regain after year one was common

3. 3

   3. Healthy low-carb diet

   Best for People who prefer fewer starches and more protein and fat

   • DIETFITS: 6.0 kg (13.2 lb) at 12 months
   • DIRECT: 4.7 kg (10.4 lb) at 2 years
   • raised HDL cholesterol in trials

   Maker-stated specs

   Price No fee; meat, fish and nuts can cost more (checked Oct 6, 2026)

   Drawback LDL cholesterol fell less than on low-fat diets in the BMJ 2020 analysis

4. 4

   4. Meal-replacement plan (shakes or bars for some meals)

   Best for Busy people who like simple, fixed choices

   • 23 trials, 7,884 adults: about 1.4 kg (3.2 lb) more loss at 1 year than other diets
   • up to 6.1 kg (13.5 lb) more with extra support

   Maker-stated specs

   Price Shake or bar costs vary by brand (checked Oct 6, 2026)

   Drawback You still have to plan the regular meals, and long-term use is a habit to think through

5. 5

   5. Healthy low-fat diet

   Best for People who like grains, beans, fruit and vegetables

   • DIETFITS: 5.3 kg (11.7 lb) at 12 months
   • BMJ 2020: largest LDL cholesterol drop of the macro patterns
   • DIRECT: 2.9 kg (6.4 lb) at 2 years

   Maker-stated specs

   Price No fee; often the cheapest pattern (checked Oct 6, 2026)

   Drawback Lost less weight than Mediterranean or low-carb in the 2-year DIRECT trial

6. 6

   6. DASH diet

   Best for People with high blood pressure or prediabetes

   • Original DASH trial lowered blood pressure within 8 weeks
   • meta-analysis: 1.4 kg (3.1 lb) more weight loss than controls over 8 to 24 weeks
   • low-calorie DASH did better still

   Maker-stated specs

   Price No fee; produce-heavy grocery list (checked Oct 6, 2026)

   Drawback Most weight data are shorter than 12 months

7. 7

   7. Higher-protein diet

   Best for People who get hungry on lower-calorie diets or want to keep muscle

   • 24 trials: 0.8 kg (1.7 lb) more loss and 0.4 kg more lean mass kept than standard protein
   • greater fullness in 3 of 5 studies

   Maker-stated specs

   Price No fee; protein foods cost more (checked Oct 6, 2026)

   Drawback Average trial lasted only about 12 weeks, so long-term results are less certain

8. 8

   8. Intermittent fasting (time-restricted or alternate-day)

   Best for People who find a daily eating window easier than counting

   • BMJ 2025 analysis of 99 trials: all fasting styles beat no diet
   • only alternate-day fasting edged out daily calorie cutting (1.3 kg, 2.8 lb)
   • 12-month trials found no difference vs calorie counting

   Maker-stated specs

   Price No fee (checked Oct 6, 2026)

   Drawback Alternate-day fasting had the highest dropout (38%) in a year-long trial

9. 9

   9. Plant-based or vegetarian diet

   Best for People who prefer plant foods or want a lower-cost protein mix

   • 12 trials, 1,151 adults: about 2.0 kg (4.5 lb) more loss than non-vegetarian diets
   • vegan styles did best (2.5 kg)

   Maker-stated specs

   Price No fee; beans and lentils keep costs down (checked Oct 6, 2026)

   Drawback The advantage shrank to 1.1 kg (2.5 lb) in trials lasting a year or more

10. 10

    10. Ketogenic (very-low-carb) diet

    Best for People who do well with very few carbs and are willing to plan carefully

    • 13 trials of 12 months or more: 0.9 kg (2.0 lb) more loss than low-fat
    • lower triglycerides and higher HDL

    Maker-stated specs

    Price No fee; specialty foods can add up (checked Oct 6, 2026)

    Drawback Raised LDL cholesterol on average, and very-low-carb eating is hard to keep up

All 10 diets side by side

#	Pick	Best for	Key specs (maker-stated)	Price range	Last checked
1	Mediterranean diet	Long-term weight loss with heart benefits	2-year trial: 4.4 kg (9.7 lb) average loss; PREDIMED: about 30% fewer major heart events vs a reduced-fat diet; only diet whose heart-risk benefits lasted at 12 months in the BMJ 2020 analysis	No fee; ordinary groceries (olive oil, nuts and fish can raise the bill)	Oct 6, 2026
2	Reduced-calorie diet, any macro mix	People who want flexibility and to eat foods they already like	POUNDS LOST: 811 adults, 2 years, similar loss with 35% to 65% carbohydrate; about 4 kg (9 lb) average loss in completers; 14% to 15% lost at least 10% of body weight	No fee; ordinary groceries	Oct 6, 2026
3	Healthy low-carb diet	People who prefer fewer starches and more protein and fat	DIETFITS: 6.0 kg (13.2 lb) at 12 months; DIRECT: 4.7 kg (10.4 lb) at 2 years; raised HDL cholesterol in trials	No fee; meat, fish and nuts can cost more	Oct 6, 2026
4	Meal-replacement plan (shakes or bars for some meals)	Busy people who like simple, fixed choices	23 trials, 7,884 adults: about 1.4 kg (3.2 lb) more loss at 1 year than other diets; up to 6.1 kg (13.5 lb) more with extra support	Shake or bar costs vary by brand	Oct 6, 2026
5	Healthy low-fat diet	People who like grains, beans, fruit and vegetables	DIETFITS: 5.3 kg (11.7 lb) at 12 months; BMJ 2020: largest LDL cholesterol drop of the macro patterns; DIRECT: 2.9 kg (6.4 lb) at 2 years	No fee; often the cheapest pattern	Oct 6, 2026
6	DASH diet	People with high blood pressure or prediabetes	Original DASH trial lowered blood pressure within 8 weeks; meta-analysis: 1.4 kg (3.1 lb) more weight loss than controls over 8 to 24 weeks; low-calorie DASH did better still	No fee; produce-heavy grocery list	Oct 6, 2026
7	Higher-protein diet	People who get hungry on lower-calorie diets or want to keep muscle	24 trials: 0.8 kg (1.7 lb) more loss and 0.4 kg more lean mass kept than standard protein; greater fullness in 3 of 5 studies	No fee; protein foods cost more	Oct 6, 2026
8	Intermittent fasting (time-restricted or alternate-day)	People who find a daily eating window easier than counting	BMJ 2025 analysis of 99 trials: all fasting styles beat no diet; only alternate-day fasting edged out daily calorie cutting (1.3 kg, 2.8 lb); 12-month trials found no difference vs calorie counting	No fee	Oct 6, 2026
9	Plant-based or vegetarian diet	People who prefer plant foods or want a lower-cost protein mix	12 trials, 1,151 adults: about 2.0 kg (4.5 lb) more loss than non-vegetarian diets; vegan styles did best (2.5 kg)	No fee; beans and lentils keep costs down	Oct 6, 2026
10	Ketogenic (very-low-carb) diet	People who do well with very few carbs and are willing to plan carefully	13 trials of 12 months or more: 0.9 kg (2.0 lb) more loss than low-fat; lower triglycerides and higher HDL	No fee; specialty foods can add up	Oct 6, 2026

Why the Mediterranean diet is number 1

The Mediterranean diet is built on vegetables, fruit, whole grains, beans, fish, nuts and olive oil. It wins on our first two criteria together. For weight, the two-year DIRECT trial (322 adults) found an average loss of 4.4 kg on a calorie-restricted Mediterranean diet, compared with 2.9 kg on a low-fat diet; adherence was 85% at two years. For health, the PREDIMED trial followed 7,447 people at high heart risk for a median of 4.8 years: major cardiovascular events were about 30% lower with a Mediterranean diet plus extra-virgin olive oil or nuts than with a reduced-fat diet (hazard ratios 0.69 and 0.72). The BMJ 2020 analysis also found it was the only pattern whose heart-risk improvements lasted at 12 months.

Low-fat, calorie-restricted6.4 lb

Mediterranean, calorie-restricted9.7 lb

Low-carb, no calorie limit10.4 lb

DIRECT trial: average weight loss after 2 years

Item	Value
Low-fat, calorie-restricted	6.4 lb
Mediterranean, calorie-restricted	9.7 lb
Low-carb, no calorie limit	10.4 lb

Reported as 2.9, 4.4 and 4.7 kg (all randomized participants). 86% of participants were men.

Source: Shai I et al., New England Journal of Medicine 2008 (DIRECT, 322 adults) (checked on October 6, 2026)

Low-carb lost slightly more weight in DIRECT, so why is it third? The 2-year results for Mediterranean and low-carb were close, and the Mediterranean diet has hard-outcome evidence (fewer heart attacks and strokes) that low-carb does not have, plus a better LDL cholesterol profile. Under our order, a close tie on weight goes to the diet with stronger health-marker evidence.

The middle of the list: flexible, simple and structured

A reduced-calorie diet with any macro mix (number 2) is the most flexible choice. POUNDS LOST showed that when calories are cut, the split of fat, protein and carbohydrate matters little for weight over two years. Our calorie deficit guide and calorie calculator show where to start. Its weakness is effort: tracking takes time, and weight regain after the first year was common in every arm.

Healthy low-carb (number 3) means fewer refined starches and sugars with plenty of vegetables, protein and unsaturated fats, not a very-low-carb keto plan. It did slightly better than low-fat in both DIETFITS and DIRECT, though the DIETFITS difference was not significant.

Meal-replacement plans (number 4) have some of the strongest one-year data of any approach: a 2019 meta-analysis of 23 trials and 7,884 adults found 1.44 kg more weight loss at one year than other diets, 2.22 kg more when both groups had support, and 6.13 kg more when the meal-replacement group also had extra support. They rank below the top three because they are a tool rather than a long-term eating pattern, and the health-marker evidence is thinner. Products vary a lot, so check protein, fiber and sugar on the label.

Healthy low-fat (number 5) produced the largest drop in LDL cholesterol among the macro patterns in the BMJ analysis and 5.3 kg of loss in DIETFITS, but it trailed in the two-year DIRECT trial. DASH (number 6) is the strongest choice if blood pressure is your main concern: the original 1997 trial lowered it within eight weeks, and a 2016 meta-analysis found 1.42 kg more weight loss than control diets over 8 to 24 weeks. It sits at 6 only because most of its weight data are shorter than our 12-month bar.

Higher protein, fasting, plant-based and keto

A higher-protein diet (number 7) adds modest benefits: in 24 trials with 1,063 people, it led to 0.79 kg more weight loss, 0.87 kg more fat loss and 0.43 kg more lean mass kept than a standard-protein diet with the same calories. The trials averaged about 12 weeks, so the long-term picture is less certain. Our protein calculator estimates a daily range.

Intermittent fasting (number 8) works about as well as daily calorie cutting. A 2025 BMJ network meta-analysis of 99 trials and 6,582 adults found that every fasting style beat eating freely, but only alternate-day fasting beat daily calorie restriction, by 1.29 kg, mostly in shorter trials. In trials of 24 weeks or more, no fasting style beat calorie restriction. Our comparison of intermittent fasting vs calorie counting goes through the trials one by one.

A plant-based or vegetarian diet (number 9) beat non-vegetarian diets by about 2.0 kg in a 12-trial meta-analysis, with vegan diets doing best, but the advantage was 1.13 kg in trials of a year or more. The keto diet (number 10) did produce 0.91 kg more weight loss than low-fat diets in 13 trials lasting at least a year, with better triglycerides and HDL, but LDL cholesterol rose on average, and very-low-carb eating is hard to sustain. If you take diabetes or blood pressure medicines, talk with your clinician before starting it.

How to choose the right diet for you

If you are not sure where to begin, Find My Options asks a few questions about your goals and preferences. To make any diet easier, build meals around high-volume, high-protein foods from our best filling foods list, and see the wider nutrition hub for meal ideas.

What no diet can do

No eating pattern on this list removes fat from one chosen body area, speeds up your metabolism in a big way, or keeps weight off without ongoing habits. In long trials such as POUNDS LOST, weight regain began after the first year, whatever the diet. Planning for keeping weight off from the start (regular weigh-ins, steady activity, a pattern you enjoy) matters as much as the choice of diet. For people with obesity-related health conditions, diet can be combined with medical treatment; see our lose weight hub for every option.

Questions to ask a professional

• Given my blood pressure, cholesterol and blood sugar, which eating pattern would help me most?
• Do any of my medicines need adjusting if I cut carbohydrates or calories?
• What calorie and protein targets make sense for me?
• Could a registered dietitian help me adapt one of these diets to my budget and culture?
• How should we measure progress besides the scale?

Frequently asked questions

What is the best diet for weight loss?

Long trials show most well-designed diets lose similar amounts of weight at one year. Ranked by long-term evidence and health benefits, the Mediterranean diet comes first, but the best diet for you is the one you can keep.

Is low-carb better than low-fat for weight loss?

Slightly, in some trials, but not by much. In DIETFITS the difference at 12 months was 0.7 kg and not significant; in DIRECT, low-carb lost 4.7 kg vs 2.9 kg for low-fat at two years.

How much weight can I expect to lose on a diet?

In long trials, average losses were about 3 to 6 kg (7 to 13 pounds) at one to two years, with a wide range between people. Group support and sticking with the plan were linked to more loss.

Is keto safe for weight loss?

Many people follow it safely, but LDL cholesterol rose on average in trials, and very-low-carb eating can interact with diabetes and blood pressure medicines. Check with a clinician first if you take those.

Does intermittent fasting work better than counting calories?

Not in trials lasting six months or longer: both worked about equally. Alternate-day fasting had a small edge in shorter trials, but more people dropped out of it.

References

1. Ge L, Sadeghirad B, Ball GDC, et al.. Comparison of dietary macronutrient patterns of 14 popular named dietary programmes for weight and cardiovascular risk factor reduction in adults: systematic review and network meta-analysis of randomised trials. BMJ, 2020. doi:10.1136/bmj.m696 · PMID 32238384 (accessed October 7, 2026) Meta-analysis
2. Gardner CD, Trepanowski JF, Del Gobbo LC, et al.. Effect of Low-Fat vs Low-Carbohydrate Diet on 12-Month Weight Loss in Overweight Adults (DIETFITS randomized clinical trial). JAMA, 2018. doi:10.1001/jama.2018.0245 · PMID 29466592 · NCT01826591 (accessed October 7, 2026) Randomized trial
3. Sacks FM, Bray GA, Carey VJ, et al.. Comparison of weight-loss diets with different compositions of fat, protein, and carbohydrates (POUNDS LOST). New England Journal of Medicine, 2009. doi:10.1056/NEJMoa0804748 · PMID 19246357 · NCT00072995 (accessed October 6, 2026) Randomized trial
4. Shai I, Schwarzfuchs D, Henkin Y, et al.. Weight loss with a low-carbohydrate, Mediterranean, or low-fat diet (DIRECT). New England Journal of Medicine, 2008. doi:10.1056/NEJMoa0708681 · PMID 18635428 · NCT00160108 (accessed October 7, 2026) Randomized trial
5. Estruch R, Ros E, Salas-Salvadó J, et al.. Primary Prevention of Cardiovascular Disease with a Mediterranean Diet Supplemented with Extra-Virgin Olive Oil or Nuts (PREDIMED, republished). New England Journal of Medicine, 2018. doi:10.1056/NEJMoa1800389 · PMID 29897866 (accessed October 6, 2026) Randomized trial
6. Astbury NM, Piernas C, Hartmann-Boyce J, et al.. A systematic review and meta-analysis of the effectiveness of meal replacements for weight loss. Obesity Reviews, 2019. doi:10.1111/obr.12816 · PMID 30675990 (accessed October 7, 2026) Meta-analysis
7. Appel LJ, Moore TJ, Obarzanek E, et al.. A clinical trial of the effects of dietary patterns on blood pressure (DASH). New England Journal of Medicine, 1997. doi:10.1056/NEJM199704173361601 · PMID 9099655 (accessed October 6, 2026) Randomized trial
8. Soltani S, Shirani F, Chitsazi MJ, Salehi-Abargouei A. The effect of dietary approaches to stop hypertension (DASH) diet on weight and body composition in adults: a systematic review and meta-analysis of randomized controlled clinical trials. Obesity Reviews, 2016. doi:10.1111/obr.12391 · PMID 26990451 (accessed October 6, 2026) Meta-analysis
9. Wycherley TP, Moran LJ, Clifton PM, Noakes M, Brinkworth GD. Effects of energy-restricted high-protein, low-fat compared with standard-protein, low-fat diets: a meta-analysis of randomized controlled trials. American Journal of Clinical Nutrition, 2012. doi:10.3945/ajcn.112.044321 · PMID 23097268 (accessed October 7, 2026) Meta-analysis
10. Semnani-Azad Z, Khan TA, Chiavaroli L, et al.. Intermittent fasting strategies and their effects on body weight and other cardiometabolic risk factors: systematic review and network meta-analysis of randomised clinical trials. BMJ, 2025. doi:10.1136/bmj-2024-082007 · PMID 40533200 (accessed October 7, 2026) Meta-analysis
11. Trepanowski JF, Kroeger CM, Barnosky A, et al.. Effect of Alternate-Day Fasting on Weight Loss, Weight Maintenance, and Cardioprotection Among Metabolically Healthy Obese Adults: A Randomized Clinical Trial. JAMA Internal Medicine, 2017. doi:10.1001/jamainternmed.2017.0936 · PMID 28459931 · NCT00960505 (accessed October 7, 2026) Randomized trial
12. Huang RY, Huang CC, Hu FB, et al.. Vegetarian Diets and Weight Reduction: a Meta-Analysis of Randomized Controlled Trials. Journal of General Internal Medicine, 2016. doi:10.1007/s11606-015-3390-7 · PMID 26138004 (accessed October 6, 2026) Meta-analysis
13. Bueno NB, de Melo IS, de Oliveira SL, da Rocha Ataide T. Very-low-carbohydrate ketogenic diet v. low-fat diet for long-term weight loss: a meta-analysis of randomised controlled trials. British Journal of Nutrition, 2013. doi:10.1017/S0007114513000548 · PMID 23651522 (accessed October 7, 2026) Meta-analysis

Facts checked on October 6, 2026

Educational information, not medical advice. Talk with a qualified healthcare professional about your own situation. In an emergency call 911.