I’m often asked how to target weight loss to a particular problem area. Unfortunately, for the most part, this isn’t possible—when the body needs energy, it will break down fat from wherever it happens to be stored, and release the free fatty acids into the bloodstream. From there, these get converted into energy via the mitochondria. When you first begin a weight loss program, including a healthy diet and exercise program, you’ll most likely notice fat loss from wherever you carry the majority of your weight first, just by the law of probabilities.

But what if you succeed in slimming down and toning up everywhere except that one problem area—the excess belly flab, your hips and thighs, or your double chin?

Some interesting studies indicate that there might be something non-invasive that you can do to target that particular spot.

Brown Fat vs White Fat

When we talk about fat loss, we mean subcutaneous (beneath the skin) white fat, or adipocytes. Fat cells are metabolically active and produce a variety of hormones, but its essential function is that of energy storage. It’s profoundly efficient, too: when one glucose molecule enters the mitochondria for energy production, it yields 38 ATP molecules (the body’s energy currency). When one fatty acid enters the mitochondria for energy production, the yield is 129 ATP.

However, this conversion of fat into energy only occurs when needed. If you consume enough calories to satisfy your daily metabolic needs, you won’t touch your extra stores of white fat. If you consume calories in excess of your daily metabolic needs, you’ll add to it.

Brown fat, by contrast, produces a different result. The density of mitochondria in brown fat is higher than in other cells, and those mitochondria have also adapted to include a higher than usual amount of uncoupling proteins (UCPs) at the very end of the electron transport chain. Uncoupling proteins are so named because rather than combining protons to turn chemical energy into ATP, they “uncouple,” or separate them, letting the same chemical energy instead dissipate as heat.

All of us have some brown fat: uncoupling proteins and subsequent heat production is what makes us “warm blooded.” Animals that live in cold regions have adapted to have a higher amount of brown fat than animals that live in warmer climates, for obvious reasons: it helps them to stay warm.

You can probably see where this is going. As it turns out, white fat can take on characteristics of brown fat in response to cold stimulation.

How Cold Exposure Affects Adipocytes

White fat that’s taken on brown characteristics is called beige fat. It doesn’t even take that profound a cold exposure to trigger this: less than ten degrees can do it. Not only that, but such exposure to mild temperature drops can also positively affect hormones like leptin and adiponectin.

Cold exposure has thus been a target of research into treatments for metabolic diseases such as metabolic syndrome, obesity, and diabetes. And while it works—in animal studies, metabolic rates double in response to cold exposure–caloric intake rises to meet the deficit, and overall weight remains the same. However, utilization of glucose does remain more efficient for a short time after cold exposure.

But even if ice baths a la Wim Hof don’t necessarily lead to global weight loss by themselves, can this approach be useful for targeted body contouring?

A procedure called cryolipolysis utilizes this approach, involving cold paddles applied to the treatment area for 30 minutes to an hour. This duration and intensity leads to apoptosis of fat cells as well as some minor inflammatory side effects that go along with tissue damage. But similar (if less intense) effects should be achievable at home by turning white fat beige, using an ice pack applied to problem areas. According to Joel Green, biohacker and author of The Immunity Code, this procedure is best kept to 20-30 minutes at a time, and no more than once a month.

The Upshot

There are incredible natural health benefits to be had just from utilization of temperature differentials, from sauna to various applications of hydrotherapy. Wim Hof (the “Iceman”) popularized ice bathing for its many health benefits, and regular cold showers have been associated with longevity. So is it any wonder that something as simple as targeted ice therapy can likewise yield impressive results?