We all enjoy late night snacks, but will it make you gain fat?

does eating late at night cause weight gain

Written by Russ Howe PTI, and most recently updated 1 day ago.

5 min read

If you’ve been going to the gym for some time, then you’ve probably heard this line before:

I’m going to breakdown this popular gym myth in today’s article, and show you why you don’t need to worry about the time when it comes to eating your meals.

does eating late at night cause weight gain

Fitness magazines used to push this belief back in the 1980s and 1990s.

The theory is pretty solid, too.

Our metabolism slows down during periods of prolonged inactivity (e.g. when we sleep, or when we watch 5-hours of Netflix while lying on the couch), so any food which is eaten during these times will not be needed for energy, and will therefore be stored as fat.

This is why bodybuilders (or just people trying to lose weight) typically eat all of their meals during the day when they are more active, and then stop eating food at around 6pm.

does eating at night cause weight gain

It turns out the metabolism doesn’t work as first theorized.

A 1999 study showed that the rate at which we burn calories (your BMR) doesn’t really change much throughout the entire day, which means your body will process the calories you eat in much the same way regardless of when you eat. (1)

This research sent shockwaves through the bodybuilding world when it was first published in the European Journal of Clinical Nutrition. Long-time gym rats (myself included) insisted that “This must be wrong!”, and said we’d wait for more research to be completed before believing it.

It didn’t take long for that research to arrive, with studies in 2002 and 2003 re-confirming the facts. (2, 3)

graph showing the difference in calorie burn between smr vs bmr

There’s also a few studies out there which have looked directly at what happens when trainees eat the bulk of their calories at night.

Did they grow an extra tire on their belly?

Of course they fucking didn’t!

A monstrous 2011 trial published in Obesity had one group of trainees spreading their calorie intake evenly throughout the day, and another group of trainees eating the bulk of their calories in the evening. They discovered that both groups lost roughly the same amount of body fat over a six month period, with the evening group dropping 25lbs and the daytime group dropping 21lbs. Interestingly, the evening group also reported less hunger. (4)

The researchers concluded that there is no connection between late night eating and weight gain, and this matches the findings of several other trials on this topic. (6, 7, 8, 9, 10)

So it really is a case of the best diet is the one you can stick to, and with that in mind, I recommend scheduling your meals in a way which helps you enjoy your diet more and remain consistent. If that means eating meals after 6pm, go for it! (5)

graph showing difference in fat loss when eating throughout the day vs eating in the evening

does eating late at night make you fat

I expect that this myth will resurface at some point, because it’s been going around since the 1980s, and when it does you’ll be fully prepared to sidestep the bullshit.

Heck, just last year we saw the media go wild about this topic when they thought they’d discovered proof that eating late at night causes weight gain.

This happened after a study was published in The Endocrine Society appeared to show evidence of subjects gaining weight with late night eating, but upon further inspection we noticed that the data had been misreported. The two big flaws in this study were a) there were no restrictions placed upon total calorie intake (so while the night-time eaters gained more weight, this is because they ate more food) and b) the study only lasted seven days, which is far too short to draw any solid conclusions from. (11)

Quite frankly, you could skew those results with one big poo.


  1. Seale J. L., et al. Relationship between overnight energy expenditure and BMR measured in a room-sized calorimeter. Eur J Clin Nutr (1999).
  2. Zhang K, et al. Sleeping metabolic rate in relation to body mass index and body composition. Int J Obes Relat Metab Disord (2002).
  3. Mischler I, et al. Prolonged daytime exercise repeated over 4 days increases sleeping heart rate and metabolic rate. Can J Appl Physiol (2003).
  4. Sofer S, et al. Greater weight loss and hormonal changes after 6 months diet with carbohydrates eaten mostly at dinner. Obesity (2011).
  5. Howell S., et al. “Calories in, calories out” and macronutrient intake: the hope, hype, and science of calories. Am J Physiol Endocrinol Metab (2017).
  6. Stratton M. T., et al. Four Weeks of Time-Restricted Feeding Combined with Resistance Training Does Not Differentially Influence Measures of Body Composition, Muscle Performance, Resting Energy Expenditure, and Blood Biomarkers. Nutrients (2020).
  7. Tinsley G. M., et al. Time-restricted feeding plus resistance training in active females: a randomized trial. Am J Clin Nutr (2019).
  8. Seimon R. V., et al. Do intermittent diets provide physiological benefits over continuous diets for weight loss? A systematic review of clinical trials. Mol Cell Endocrinol (2015).
  9. Sensi S., et al. Chronobiological aspects of weight loss in obesity: effects of different meal timing regimens. Chronobiol Int (1987).
  10. Nonino-Borges C. B., et al. Influence of meal time on salivary circadian cortisol rhythms and weight loss in obese women. Nutrition (2007).
  11. Zaman A., et al. Eating later in the day may be associated with obesity. The Endocrine Society (2019).

Website members are killing these russhowepti.com training programs, and you can start today!

Full-Body Blitz

Chisel your leanest body to date with this 6-week full-body workout program which is suitable for both beginner and advanced trainees.

RPE 20

Use the Rest Pause technique to add slabs of lean muscle to your fame over the next 10-weeks.

Classic Size

This is an old school 12-week program which uses dropsets, rest pause sets, and classic linear periodization to help you pack on serious muscle mass.

Become War

Carve your action hero body with my modernized version of Sly’s insane Rambo II training regimen!

Get More From Russ!


I’m Russ. I’ve been a personal trainer since 2002, and I own russhowepti.com.

My job is to simplify fitness for my readers.

I send out free fitness tips to over 100,000 men and women every week, all in the same no-nonsense style as the article you’ve just read, so if you enjoyed reading it be sure to jump on my email list below.

Leave a Reply

Your email address will not be published. Required fields are marked *

Join Up

russ howe pti programs

Get all of my detailed workout plans and easy-to-use nutrition plans by joining up below.

Click here to join.

Newest Programs

  • Chisel
  • MuscleMania workout program Russ Howe PTI
  • train to success
  • russ howe pti full-body blitz

Click here to see all programs.

Newest Blogs