Can You Burn Fat Without Being in Ketosis?

When you're trying to lose weight, what you really want is to lose fat while preserving your lean muscle mass. Ketosis occurs when the body burns fat at a high rate. Lowering your carbohydrate intake gets you into the fat-burning zone, but you don't necessarily have to be in ketosis to achieve this goal.

Ketosis means that your body is burning fat at high enough rates that you have a lot of ketone bodies, waste compounds produced during the burning of fat. These ketone bodies can also be burned for energy by your brain and most of your other body cells. To have ketone levels high enough to be detectable, you need to keep your carbohydrate intake lower than 50 grams per day, according to the Food and Agriculture Organization of the United Nations. If you are in ketosis, which can be verified by using urine ketone strips, you can be 100 percent sure that your body is in fat-burning mode.

During a study published in 2005 in the "Journal of the American Medical Association," researchers compared different diet plans, finding that people can lose fat without being in ketosis. If your carb intake is too high, your body prioritizes burning these carbs first. You can promote fat burning by decreasing your carbohydrate intake, but you don't necessarily need to go as low as required to be in ketosis. Restrict your carbs slightly to help your body switch into fat-burning mode more easily.

You can burn fat even if you're not producing ketones as long as you create a calorie deficit. In other words, if you eat slightly less than your body needs, your body must gain energy from somewhere else, such as the fat in your love handles. To burn more fat, cut down on your portion sizes, especially of carbohydrate-rich foods such as sweets, soft drinks, bread, pasta, rice and potatoes. Be reasonable about your calorie intake, however. If you restrict your calorie intake too dramatically, your body might start burning muscle instead of fat.

Even if your total body weight is the same on the scale, you could still be burning and losing fat without being in ketosis. Because 1 lb. of muscle takes less room than 1 lb. of fat but weighs the same on the scale, take your measurements and notice how your clothes fit. Measure your chest, waist, hips, thighs and arms every couple of weeks to see if you are losing fat. If nothing happens, look at your food intake to see if you can reduce your serving sizes or carb intake a little bit more until your body starts burning fat.