GUIDES

How to choose a diet

Five questions, your health, your daily life: a practical way to find a diet you’ll keep

Five questions to ask yourself

Five questions

  1. What’s your goal? Weight loss, lower blood pressure, heart health or better blood sugar each point to different diets. Most people have more than one goal; start with the one that matters most to you.
  2. Which foods do you enjoy? A diet that removes your favorite foods is hard to keep. If you love bread and pasta, keto will be a struggle; if you love meat and cheese, a vegan diet may be.
  3. How do you live? Long workdays, shift work, family meals, travel and eating out favor flexible diets with simple rules.
  4. How much do you cook? Some diets, such as DASH and plant-based, work best with home cooking; calorie counting and intermittent fasting work with any food.
  5. What does your health need? Medication, diabetes, kidney disease, pregnancy or a history of eating disorders can rule some diets out.

Match the diet to your health

If you have a health condition, the evidence points more clearly in some directions. These are the strongest findings:

  • High blood pressure: DASH lowered blood pressure by 11.4/5.5 mmHg in people with hypertension within weeks, and eating less salt lowered it further 2,3.
  • Heart disease, or a high risk of it: the Mediterranean diet has the strongest trial evidence for preventing heart attacks and strokes, both before and after a first heart problem 4,5.
  • Type 2 diabetes: low-carb diets helped more people reach remission at 6 months 6, and keto and Mediterranean diets lowered blood sugar similarly 7. Plan any change with your doctor, as medication may need adjusting.
  • High LDL cholesterol: be careful with keto, which raises LDL in some people 8; the Mediterranean diet lowers it 9.
  • Kidney disease: avoid high-protein diets unless your doctor agrees.
  • Pregnancy, breastfeeding or a history of eating disorders: don’t diet or fast without medical advice.

If you want…

A starting point, not a rule: many people combine two.
If you wantTry
Lower blood pressureDASH
Better heart healthMediterranean or plant-based
To lose weight and feel fullHigh-protein or low-carb
Freedom to eat anythingCalorie counting or intermittent fasting
No counting at allIntermittent fasting or Mediterranean
A strict, structured planKeto, with medical advice

Match the diet to your daily life

Practical fit matters as much as the evidence.
Your situationDiets that tend to fitWhy
You rarely cookCalorie counting, intermittent fastingThey work with any food, including ready meals
You cook for a familyMediterranean, DASHEveryone can eat the same meals
You often eat outIntermittent fasting, calorie countingSimple rules travel well
Your budget is tightPlant-based built on beans and grainsLegumes, oats and rice are among the cheapest foods
You train hardHigh-proteinProtein supports muscle repair and growth 10
You get very hungry on dietsHigh-protein, low-carbProtein is the most filling nutrient 11

Test it for a month

Signs a diet isn’t right for you

  • You’re hungry most of the day, or thinking about food constantly.
  • You feel tired, dizzy or cold for more than the first week or two.
  • You’re skipping social events to stay on plan.
  • You binge after days of strict eating.
  • Your mood or sleep has got worse.

Myths and facts

Myth The diet that worked for my friend will work for me.

Fact Results vary a lot from person to person on every diet, and tests of genes and insulin didn’t predict who does better on which 12. Try what suits your tastes.

Myth A diet has to be hard to work.

Fact The strictest diets had the most dropouts in a year-long trial, and the people who stuck with any diet did best 1.

Myth You have to pick just one diet.

Fact Diets combine well: Mediterranean with high protein, DASH with an eating window, low-carb with calorie counting.

Questions

Can I combine two diets?

Yes. Mediterranean and DASH overlap a lot, high-protein fits with most diets, and an eating window fits with all of them.

How long should I try a diet?

At least four weeks. Early changes on the scale are often water, so judge by your trend over a month and how you feel.

Should I see a dietitian?

If you have a health condition, take medication or have struggled with eating, a registered dietitian or your doctor can tailor a plan to you.

Sources

  1. Dansinger ML, Gleason JA, Griffith JL, et al. Comparison of the Atkins, Ornish, Weight Watchers, and Zone Diets for Weight Loss and Heart Disease Risk Reduction: A Randomized Trial. JAMA. 2005;293(1):43-53. doi.org/10.1001/jama.293.1.43
  2. Appel LJ, Moore TJ, Obarzanek E, et al. A Clinical Trial of the Effects of Dietary Patterns on Blood Pressure. N Engl J Med. 1997;336(16):1117-1124. doi.org/10.1056/NEJM199704173361601
  3. Sacks FM, Svetkey LP, Vollmer WM, et al. Effects on Blood Pressure of Reduced Dietary Sodium and the Dietary Approaches to Stop Hypertension (DASH) Diet. N Engl J Med. 2001;344(1):3-10. doi.org/10.1056/NEJM200101043440101
  4. 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. N Engl J Med. 2018;378(25):e34. doi.org/10.1056/NEJMoa1800389
  5. Delgado-Lista J, Alcala-Diaz JF, Torres-Peña JD, et al. Long-term secondary prevention of cardiovascular disease with a Mediterranean diet and a low-fat diet (CORDIOPREV): a randomised controlled trial. Lancet. 2022;399(10338):1876-1885. doi.org/10.1016/S0140-6736(22)00122-2
  6. Goldenberg JZ, Day A, Brinkworth GD, et al. Efficacy and safety of low and very low carbohydrate diets for type 2 diabetes remission: systematic review and meta-analysis of published and unpublished randomized trial data. BMJ. 2021;372:m4743. doi.org/10.1136/bmj.m4743
  7. Gardner CD, Landry MJ, Perelman D, et al. Effect of a ketogenic diet versus Mediterranean diet on glycated hemoglobin in individuals with prediabetes and type 2 diabetes mellitus: The interventional Keto-Med randomized crossover trial. Am J Clin Nutr. 2022;116(3):640-652. doi.org/10.1093/ajcn/nqac154
  8. Bueno NB, de Melo ISV, de Oliveira SL, et al. Very-low-carbohydrate ketogenic diet v. low-fat diet for long-term weight loss: a meta-analysis of randomised controlled trials. Br J Nutr. 2013;110(7):1178-1187. doi.org/10.1017/S0007114513000548
  9. 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;369:m696. doi.org/10.1136/bmj.m696
  10. Morton RW, Murphy KT, McKellar SR, et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med. 2018;52(6):376-384. doi.org/10.1136/bjsports-2017-097608
  11. Weigle DS, Breen PA, Matthys CC, et al. A high-protein diet induces sustained reductions in appetite, ad libitum caloric intake, and body weight despite compensatory changes in diurnal plasma leptin and ghrelin concentrations. Am J Clin Nutr. 2005;82(1):41-48. doi.org/10.1093/ajcn/82.1.41
  12. 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 and the Association With Genotype Pattern or Insulin Secretion: The DIETFITS Randomized Clinical Trial. JAMA. 2018;319(7):667-679. doi.org/10.1001/jama.2018.0245

MAKE IT A HABIT

Any diet.
Your eating window.

Fasting Tracker is a free intermittent fasting app for iPhone, iPad and Apple Watch.

Download Fasting Tracker
Fasting Tracker on iPhone 18 Pro during a 16:8 fast: Sunny in the middle of the ring, 11 hours 30 minutes elapsed, 71 percent of the goal, a 9-day streak and the current stage, Blood Sugar Falling

dieting.app is general information, not medical advice. If you are pregnant or breastfeeding, have diabetes, kidney disease or a history of eating disorders, or take medication, talk to your doctor before changing how you eat.