How to lose belly fat: what the spot-reduction trials found, and what takes it off instead

"Belly fat" is two kinds of fat. One sits under the skin of your stomach, the layer you can pinch. The other sits deeper, inside the abdomen, and it takes a scan to measure it; studies call it visceral fat.¹ Both come up in the trials below. Most belly-fat advice is a list of ab exercises, and that's the part the trials tested most directly.

It's a page about how belly fat comes off, not a promise about how much or how soon. The studies below measured groups of people, most of them small.

What happened when people trained one spot

Training a muscle to lose the fat over it is called spot reduction. These are the trials that tested it:

• Abs, six weeks. In a 2011 trial of 24 sedentary adults (14 men, 10 women), the group that did seven ab exercises five days a week saw no significant effect on abdominal fat, waist size or the skinfolds over the stomach compared with a group that didn't, though its curl-ups improved.²
• Abs on top of a diet, 12 weeks. In a 2015 trial, 40 overweight and obese women dieted, and half also did ab resistance training. Both groups lost abdominal fat under the skin, measured by ultrasound; the ab training made no significant difference.³
• One leg, 12 weeks. In a 2013 trial, 11 young adults trained only one leg, with very long sets on a leg press. Their fat mass went down overall, and the fat that came off was in the arms and trunk, not in the trained leg.⁴
• One arm, 12 weeks. In a 2007 study of 104 adults (45 men, 59 women) who trained only one arm, MRI found fat loss spread across both arms rather than concentrated in the trained one. A single skinfold did show a drop in the trained arm in the men; the authors read the MRI result as supporting the notion that spot reduction doesn't occur.⁵
• A circuit, eight weeks. In a 2021 trial, 14 adults with no more than a year of training experience were randomly assigned to the same exercises in two orders: ab and triceps exercises alternated with cardio in a circuit, or the cardio first and the weights after. Only the circuit group's body mass and the fat under the skin of the upper abdomen, measured by ultrasound, went down significantly, and so did the fat at a site over the back muscles. Those were changes within each group; the paper doesn't report a significant difference between the two groups. The authors named the small number of participants as a limitation.⁶
• Energy-matched, ten weeks. In a 2023 trial, 16 overweight men either ran or swapped part of the running for crunches and torso rotations, with the two programs matched for energy cost. The ab group lost more fat from the trunk, while total fat loss was similar; the authors concluded that spot reduction exists in adult men. Its ab sessions ran almost twice as long to burn the same energy.⁷

Read together: in most of these trials, training one spot didn't take the fat off that spot first. Two small trials that mixed ab work into cardio found signs of a local effect at the trunk: in the energy-matched one, in men, more trunk fat came off than with running alone; in the circuit one, the drop was within the circuit group only. None of them showed ab work standing in for a calorie deficit. Train your abs for the muscle (how to get a six pack covers that side), not to burn the fat over it.

What takes belly fat off

The same thing that takes fat off anywhere: using more energy than you take in. Body weight change is associated with an imbalance between the energy in the food you eat and the energy your body spends.⁸ The short list, each piece explained on how to lose body fat:

1. A small calorie deficit. Estimate maintenance, eat a little under it, adjust from the trend: calories and protein.
2. Lifting. Diet-induced weight loss reduces muscle mass, and exercise, resistance exercise included, helps preserve it.⁹ Start with how to start lifting weights.
3. Enough protein, toward the higher end of this site's range while you're in a deficit (calories and protein).
4. Daily movement. Steps are the easiest part to keep: walking for fat loss.
5. Sleep, and a weekly trend instead of a daily verdict: why you can't lose fat.

The deeper fat: what exercise did in the scans

For the fat inside the abdomen, the evidence comes from scans. A 2013 meta-analysis of 15 studies with 852 overweight adults, with no calorie cut, found that exercise reduced visceral fat as measured, and that aerobic training at moderate or high intensity showed the most potential to reduce it, in men and in women.¹ That's a measurement on a scanner, not a promise about your waist. What counts as moderate, and how many minutes: how much cardio per week.

Love handles

Love handles are the fat at the sides of your waist, over the obliques. The trials above apply to them the same way: oblique exercises train the obliques, and the fat over them comes off with the rest. Train the obliques for strength (the side plank, the cable woodchopper, the Pallof press) and take the fat off with the list above.

How to tell it's coming off

A tape measure is the simplest tool you have for belly fat. Measure your waist at the same spot, at the same time of day, once a week, and add photos in the same light and a weekly weight average. A single morning tells you little. How to know it's working lays the measures out.

Common questions

How do you lose belly fat fast, or in a week?

There's no honest timeline, and none of the trials above gives one. How quickly fat comes off, and from where first, differs from person to person. What you control is the list above, done every week, and a tape measure to tell you whether it's working.

Do crunches burn belly fat?

Not on their own, in the trials that tested them. Six weeks of ab exercises had no significant effect on abdominal fat, and adding ab training to a diet made no significant difference to the fat under the skin of the stomach.^2,3 The two small trials that found signs of a local effect at the trunk mixed ab work into cardio (above). Crunches train the muscle, and that's a reason to do them.

How do men lose belly fat? How do women?

The same way. The trials above included men and women, and in the 2013 meta-analysis aerobic training reduced visceral fat in both.^2,5,1 Training for women specifically: strength training for women.

How do you lose belly fat naturally?

Everything on this page is food, training, steps and sleep. It doesn't cover supplements, products or medication; if you're considering any of them, that's a question for your doctor.

How do you lose love handles?

Like the rest of your belly fat: the whole-body list above. Oblique exercises train the muscle underneath; in the one-arm and one-leg trials, training a spot didn't take the fat off that spot first.^4,5

How do you lose arm fat, or thigh fat?

The same way as belly fat: the whole-body list above, not exercises for that one spot. In the one-arm trial, 104 adults trained only their non-dominant arm for 12 weeks, and MRI found the changes in the fat under the skin didn't differ between the trained arm and the other one; a single skinfold did drop in the trained arm in the men.⁵ In the one-leg trial, 11 young adults trained only one leg, and the fat that came off was in the arms and trunk, not in the trained leg.⁴ Arm and leg exercises still train the muscle underneath: the arm workout and the leg day workout.

How do you get a flat stomach?

With the same whole-body list, not with ab exercises alone, and none of the trials above gives a timeline for it. In the six-week trial, seven ab exercises five days a week had no significant effect on abdominal circumference or the skinfolds at the stomach and above the hip, though the exercisers' curl-ups improved.² So train your abs for the muscle, work the list above every week, and let the tape measure tell you whether your waist is changing.

If you'd rather have someone read the tape

None of this is a secret; holding a small deficit, a lifting program and your daily steps week after week is the hard part. Coaching is the version where your workouts live in Trainerize, built around the days you actually have, and someone reads your weigh-ins, photos and logged workouts every week and adjusts the plan. Fat loss coaching explains how that works, and apply is the first step. Otherwise: measure your waist this morning and write it down.