Get a free visit for ED treatment. Start now

Last updated: Mar 23, 2021
8 min read

How long does it take to lose weight?

steve silvestrochimene richa

Medically Reviewed by Steve Silvestro, MD

Written by Chimene Richa, MD


If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

If you are trying to lose weight, know that you are not alone. Almost half of American adults try to lose weight in a year (Santos, 2017). Unsurprisingly, the weight loss industry makes tons of money each year. There are pills, herbs, cleanses, detoxes, fat diets, and any number of weight loss options—some with unrealistic claims. But how long does it really take to lose weight?

Meet Plenity—an FDA-cleared weight management tool

Plenity is a prescription-only therapy that helps you manage your weight while still enjoying your meals. Find out if it’s right for you.

Learn more

What does it take to lose weight?

Most experts suggest that a healthy weight loss program should aim to help you lose about 1–2 pounds per week (NIH, 2020). How much time this takes will depend not only on the amount of weight you want to lose, but also on several other factors like gender, age, medical issues, medications, etc. (Turer, 2015). To help you understand how long your weight loss journey will take, let’s talk about how your body loses weight.

Metabolic rate

The fundamental principle of weight loss is that, to lose weight, you need to take in fewer calories than your body uses daily, also known as a calorie deficit. This makes sense when you think of the reverse—if you eat more calories than you burn, you will gain weight. 

You’re probably familiar with food calories, but what about the calories your body burns up in a day? You can measure the calories in food by knowing what’s in your meal, but it’s a bit harder to predict how many calories your body uses because there are so many factors at play, like gender, activity level, etc.

Did you know your body burns energy just by being alive? Breathing, pumping your blood to and from your heart, etc.—these actions burn a certain number of calories without you even trying. 

This is called your resting or basal metabolic rate. Resting metabolic rate accounts for 60% of the total energy you use each day. The remaining energy fuels your physical activity and the digestion and absorption of your food (Popson, 2020).

Your resting metabolic rate stays relatively constant, but it can differ for each person. Women tend to have a lower resting metabolic rate than men (Popson, 2020). Genetics may also have a role in determining resting metabolic rate, as well as the tendency towards gaining weight or obesity (Manini, 2011; Bahreynian, 2017).  

What else affects weight loss

While your metabolic rate is an important part of weight loss, it is not everything; other factors play a role as well, including diet, exercise, age, etc. (Anthanont, 2016).


There is no magic diet that guarantees permanent weight loss. It all comes down to the same fundamental principle—you need to burn more calories than you eat. Your diet should include the necessary nutrients and lower your calories while not being so restrictive that it is too hard for you to stick to it (Rynders, 2019). Some popular diet options include intermittent fasting, ketogenic diets, and the Mediterranean diet.

  • Intermittent fasting. This dieting strategy involves switching between eating and fasting, limiting your eating windows to a certain amount of time. Intermittent fasting works for weight loss because it helps you limit your calories. It’s not necessarily any better than other diets that lower your daily caloric intake, but it’s a convenient option for many people (Rynders, 2019).
  • Ketogenic diet. Also known as the “keto” diet, this eating plan encourages you to eat primarily fat, some protein, while limiting carbohydrate intake; this is one of several “low carb” diets out there. Keto diets may help with weight loss based on the theory that you can force your body into ketosis, where you burn fat for energy instead of carbohydrates. Many people have a hard time sticking to this type of diet because it is so restrictive (Abassi, 2018). 
  • Mediterranean diet. This diet is based on the eating habits of people living in Spain, Greece, Italy, and neighboring countries. It limits red meat while encouraging fruits, vegetables, whole grains, seafood, lean meats, and monounsaturated fats like olive oil. Some studies suggest that the Mediterranean diet helps you lose more weight than “low fat” diets. But the amount of weight lost is about the same as other similar diets (Mancini, 2016).


Engaging in exercise increases the number of calories that your body burns up and helps with weight loss—you lose more weight with diet and exercise than just dieting alone (Johns, 2014). 

But exercise is not just for weight loss; it also improves your overall health and wellness. The current physical activity guidelines recommend that the average adult perform 150–300 minutes of moderate exercise or cardio (like brisk walking) per week. Adding resistance training can also help increase lean muscle (HHS, 2018). 

NEAT (or non-exercise activity thermogenesis) is another way that you can increase your activity. NEAT refers to the calories you burn doing simple movements like fidgeting, singing, cleaning, and other activities of daily living. You can burn up to an additional 350 calories per day with NEAT (Chung, 2018).


Some people find it harder to lose weight as they get older. We don’t know exactly why, though, especially since it can vary from person to person. Data suggests that your metabolism and resting metabolic rate decline with age, though, so that may play a role (McMurray, 2014; St-Onge, 2010). 

Aging also tends to change your body composition; people often lose muscle mass and increase body fat as time goes on (St-Onge, 2010). However, other studies show that older people with a higher starting weight tend to lose more weight than younger people on the same diet. This could be because older people may be more motivated and stick to the long-term program (Finkler, 2012). Lastly, some research suggests that age does not play a role in keeping the weight off (Varkevissar, 2019).


As mentioned earlier, a woman’s resting metabolic rate tends to be lower than that of her male counterpart (Popson, 2020). This can partly explain why men seem to lose weight faster than women. But like everything else, when it comes to weight loss, the answer is not that simple. 

Women also have to deal with hormonal changes, like menstrual cycles, pregnancy, and menopause. Pregnancy can change the fat distribution and increase how much fat builds up around your belly. Menopause may trigger lasting weight gain due to the combination of aging and the loss of normal ovary hormone production (Perreault, 2019). 


People with disrupted sleep are at higher risk for developing obesity or other weight-related issues (Medic, 2017). Not getting enough sleep may lead to excessive eating and difficulty losing weight (Perreault, 2019). One study found that a lack of sleep increases your appetite, especially for calorie-rich, high-carbohydrate foods (Greer, 2013).


When you have high levels of stress, it can wreak havoc on your body. It also seems to play a role in losing weight. Studies have shown that increased stress leads to weight gain and makes it more challenging to lose weight. Stress may also increase your cravings for high-calorie comfort foods, like that pint of ice cream (Sinha, 2018).

Medical conditions

Several medical conditions may make losing weight harder or take longer, including (Perreault, 2019): 

  • Thyroid problems
  • Pituitary dysfunction
  • Cushing syndrome
  • Hormonal changes in women (PCOS, menopause, pregnancy)


Weight gain and difficulty losing weight is a common side effect for several types of medications, like corticosteroids, antipsychotics, and antidepressants, among others (Turer, 2015). If you suspect that any of these drugs are slowing your rate of weight loss, consult with your medical provider regarding your options.

What happens if you lose weight too fast?

As mentioned earlier, most experts recommend losing no more than 1–2 pounds per week, and there’s a good reason for this. If you lose weight too fast, you run the risk of developing both bothersome symptoms and serious medical problems, such as (Joshi, 2018):

  • Gallstones
  • Dehydration
  • Malnutrition 
  • Headaches 
  • Fatigue
  • Irritability
  • Menstrual changes

Tips for successful weight loss

Think of losing weight as a journey. There will be highs and lows, times when you feel empowered, and others when you just want to give up. But don’t get discouraged. Use the reasons that you started this weight loss journey to keep you motivated. And if you fall off the wagon, no need to call it quits. Just pick yourself up and start again. You are developing healthy habits that you can carry with you for the rest of your life.

Some people lose weight quickly in the beginning, usually water weight, and then things seem to slow down or plateau. This does not necessarily mean that your weight loss plan is not working. It’s normal for your body weight to level off, so don’t give up. Long-term weight loss, meaning weight that you lose and actually keep off, may take a year or more for some people.  

You can help yourself succeed by self-monitoring or keeping track of your foods, weigh-ins, calorie intake, etc. (Goldstein, 2019). Holding yourself accountable will encourage you to stay on track with your weight loss and hopefully keep it off in the long run (Varkevissar, 2019). 

Don’t hesitate to ask for help. Seek medical advice from your healthcare provider before starting a weight loss plan. Get the help of a nutritionist or registered dietitian, personal trainer, etc. Finding a support group can help you realize that you are not alone on this journey. 


  1. Abbasi, J. (2018). Interest in the Ketogenic Diet Grows for Weight Loss and Type 2 Diabetes. JAMA, 319(3), 215. doi: 10.1001/jama.2017.20639.
  2. Bahreynian M, Qorbani M, Khaniabadi BM, et al. (2017). Association between Obesity and Parental Weight Status in Children and Adolescents. Journal of Clinical Research in Pediatric Endocrinology, 9(2):111-117. doi: 10.4274/jcrpe.3790.
  3. Finkler, E., Heymsfield, S. B., & St-Onge, M. P. (2012). Rate of weight loss can be predicted by patient characteristics and intervention strategies. Journal of the Academy of Nutrition and Dietetics, 112(1), 75–80. doi:10.1016/j.jada.2011.08.034.
  4. Goldstein, S. P., Goldstein, C. M., Bond, D. S., Raynor, H. A., Wing, R. R., & Thomas, J. G. (2019). Associations between self-monitoring and weight change in behavioral weight loss interventions. Health psychology : Official Journal of the Division of Health Psychology, American Psychological Association, 38(12), 1128–1136. doi:10.1037/hea0000800.
  5. Greer SM, Goldstein AN, Walker MP. (2013). The impact of sleep deprivation on food desire in the human brain. Nature Communications, 4:2259. doi: 10.1038/ncomms3259.
  6. Hall, K. D., & Kahan, S. (2018). Maintenance of Lost Weight and Long-Term Management of Obesity. The Medical Clinics of North America, 102(1), 183–197. doi:10.1016/j.mcna.2017.08.012.
  7. Johns, D. J., Hartmann-Boyce, J., Jebb, S. A., Aveyard, P., & Behavioural Weight Management Review Group (2014). Diet or exercise interventions vs combined behavioral weight management programs: a systematic review and meta-analysis of direct comparisons. Journal of the Academy of Nutrition and Dietetics, 114(10), 1557–1568. doi:10.1016/j.jand.2014.07.005.
  8. Joshi, S., & Mohan, V. (2018). Pros & cons of some popular extreme weight-loss diets. The Indian Journal of Medical Research, 148(5), 642–647. doi:10.4103/ijmr.IJMR_1793_18.
  9. Mancini, J. G., Filion, K. B., Atallah, R., & Eisenberg, M. J. (2016). Systematic Review of the Mediterranean Diet for Long-Term Weight Loss. The American Journal of Medicine, 129(4), 407–415. doi: 10.1016/j.amjmed.2015.11.028.
  10. Manini, T. M., Patel, K. V., Bauer, D. C., Ziv, E., Schoeller, D. A., Mackey, D. C., Li, R., Newman, A. B., Nalls, M., Zmuda, J. M., Harris, T. B., & Health, Aging and Body Composition Study (2011). European ancestry and resting metabolic rate in older African Americans. European Journal of Clinical Nutrition, 65(6), 663–667. doi:10.1038/ejcn.2011.22.
  11. McMurray, R. G., Soares, J., Caspersen, C. J., & McCurdy, T. (2014). Examining variations of resting metabolic rate of adults: a public health perspective. Medicine and Science in Sports and Exercise, 46(7), 1352–1358. doi:10.1249/MSS.0000000000000232.
  12. Medic, G., Wille, M., & Hemels, M. E. (2017). Short- and long-term health consequences of sleep disruption. Nature and Science of Sleep, 9, 151–161. doi:10.2147/NSS.S134864.
  13. Perreault, L. (2019). Obesity in adults: Etiology and risk factors. Pi-Sunyer, F.X. and Kunins, L. (Eds.). UpToDate. Retrieved on March 9, 2021 from
  14. Popson MS, Dimri M, Borger J. Biochemistry, Heat and Calories. (2020 August). In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Available from:
  15. Rynders, C. A., Thomas, E. A., Zaman, A., Pan, Z., Catenacci, V. A., & Melanson, E. L. (2019). Effectiveness of Intermittent Fasting and Time-Restricted Feeding Compared to Continuous Energy Restriction for Weight Loss. Nutrients, 11(10), 2442. doi: 10.3390/nu11102442.
  16. Santos, I., Sniehotta, F. F., Marques, M. M., Carraça, E. V., & Teixeira, P. J. (2017). Prevalence of personal weight control attempts in adults: a systematic review and meta-analysis. Obesity Reviews : An Official Journal of the International Association for the Study of Obesity, 18(1), 32–50. doi: 10.1111/obr.12466.
  17. Sinha R. (2018). Role of addiction and stress neurobiology on food intake and obesity. Biological Psychology, 131, 5–13. doi: 10.1016/j.biopsycho.2017.05.001.
  18. St-Onge MP, Gallagher D. (2010) Body composition changes with aging: the cause or the result of alterations in metabolic rate and macronutrient oxidation? Nutrition. Feb;26(2):152-5. doi: 10.1016/j.nut.2009.07.004.
  19. Turer C. B. (2015). Tools for Successful Weight Management in Primary Care. The American Journal of the Medical Sciences, 350(6), 485–497. doi: 10.1097/MAJ.0000000000000530.
  20. Varkevisser, R., van Stralen, M. M., Kroeze, W., Ket, J., & Steenhuis, I. (2019). Determinants of weight loss maintenance: a systematic review. Obesity reviews : An Official Journal of the International Association for the Study of Obesity, 20(2), 171–211. doi: 10.1111/obr.12772.