Cold Weather Weight Loss – 376% Increase in Fat Calories Burned

I’ve known for a while now that exposure to cold climates increases metabolism. I found this journal article ( that proves my hypothesis. Here’s the summary:

Effect of cold exposure on fuel utilization in humans: plasma glucose, muscle glycogen, and lipids

Effect of cold exposure on fuel utilization in humans: plasma glucose, muscle glycogen, and lipids. J Appl Physiol 93: 77–84, 2002. First published March 1, 2002; 10.1152/japplphysiol.00773.2001.—The relative roles of circulatory glucose, muscle glycogen, and lipids in shivering thermogenesis are unclear. Using a combination of indirect calorimetry and stable isotope methodology ([U- 13C]glucose ingestion), we have quantified the oxidation rates of these substrates in men acutely exposed to cold for 2 h (liquid conditioned suit perfused with 10°C water). Cold exposure stimulated heat production by 2.6-fold and increased the oxidation of plasma glucose from 39.4 ± 2.4 to 93.9 ± 5.5 mg/min (+138%), of muscle glycogen from 126.6 ± 7.8 to 264.2 ± 36.9 mg glucosyl units/min (+109%), and of lipids from 46.9 ± 3.2 to 176.5 ± 17.3 mg/min (+376%). Despite the observed increase in plasma glucose oxidation, this fuel only supplied 10% of the energy for heat generation. The major source of carbohydrate was muscle glycogen (75% of all glucose oxidized), and lipids produced as much heat as all other fuels combined. During prolonged, low-intensity shivering, we conclude that total heat production is unequally shared among lipids (50%), muscle glycogen (30%), plasma glucose (10%), and proteins (10%). Therefore, future research should focus on lipids and muscle glycogen that provide most of the energy for heat production.

There’s a lot of math and jargon in there but in a nutshell; they put a few guys in suits that maintain 10°C or 50°F and measured the amount of energy their bodies used to maintain a core temperature of 98.6°F for two hours. The results are remarkable and very useful for those of us with a few extra pounds to lose. The men in the experiment burned 376% more fat wearing the cold suit versus sitting in an 80°F room.


Needless to say, I’ve been using this information to trim the fat. I got lazy when it started getting dark at 5:30 and started eating like crap. On New Years Day, however, I entered a Biggest Loser competition with my family members. I’ve been taking 30 minute walks in jeans, a hat, gloves and a Tshirt. It’s semi-painful, but I believe it is working.


Fat IN Your Belly Doesn’t End Up ON Your Belly

I read an interesting article on the NYT Well blog: Eating Fat, Staying Lean that contained some data from a recent Johns Hopkins study.

Kerry Stewart, director of clinical and research and exercise physiology at Johns Hopkins University School of Medicine is publishing initial findings of a long term study on diet and exercise. Study participants in the low-carb/high-fat group lost 10 pounds in an average of 45 days while it took the low-fat calorie restricted group an average of 70 days.

It’s interesting to note that in the study both groups reduced their caloric intake by about 750 calories. I’ve found if I don’t eat enough my weight loss stalls out and my metabolism (or desire to exercise) takes a nose dive. I find that restricting calories by following the calories in calories out theory of weight control leads to inferior results. It’s next to impossible to maintain any sort of exercise program without consuming enough food.

The real weight loss occurs not because of restricted calories but from the reduced insulin levels. In my post Carbs = Fatness I quoted some research that supports this. Insulin is a storage hormone, when levels are pushed higher by ingesting sugars the body stores energy as fat. To release energy or fat from your fat cells your insulin levels must be low enough for other hormones to be produced and break down fatty acids.

Fat Metabolism Blocked by Insulin

Fat metabolism can not occur when when your body is full of glucose (carbs) and thus insulin.

The image for this post is a simple illustration of insulin metabolism. When we ingest carbohydrates they are broken down into glucose and absorbed in the upper part of the small intestine. Glucose then enters the blood stream an our pancreas produces insulin which stores the glucose in our muscles as glycogen or in our fat cells as a glycerol and three fatty acids or a triglyceride. Another effect if insulin is that it lowers fat utilization through the prevention of fatty acid oxidation. Insulin prevents your from using fat as fuel.

Fat People are Starving?

Here’s another interesting point. If we are even a little bit insulin resistant, and most fat people are, then our pancreas will produce extra insulin to get our blood glucose in check. Remember, insulin stores glucose in our cells; a good thing in muscles and bad in fat cells. Well when all of the glucose has been shuttled out of the blood stream by excess insulin into our fat cells the other cells in the body start signaling for energy. However, our elevated insulin levels prevent lipolysis, or burning fat for energy, so our cells signal some more and we end up being hungry. This is a cyclical process; our fat cells soak up all the energy we ingest as food and because of elevated insulin levels there is an energy deficit for our other cells. So, you guessed it, we eat and then the process begins again.

A Caveat to Eating Fat

The title of this post is a little bit misleading unless we are eating a low-carb diet. There are all sorts of essential fats and fatty acids that you’re body requires to operate efficiently or at all. We get these from our diets and our bodies use them. A widely accepted essential fatty acid are DHA & EPA found in fish oil. Our bodies can not produce these and they must come from endogenous sources such as food. So fat in our diets is a good thing.

Here’s the caveat; if we eat a bunch of carbs the body has to take care of those or try to use them for energy. In that case, then yes, the excess fat in our diets is stored along with the carbs through lipogenesis because we’ve created an energy surplus. Without carbs fueling an insulin response our bodies store much less energy as fat.

Our Bodies Prefer Low-Carb

Writing the previous paragraphs reminded me of another interesting evil of low-fat diets. There is a myriad of essential fatty (EFAs) andamino acids. I won’t go into them in depth here but check the links for the Wikipedia articles. Also, according to Wikipedia (as well as every medical textbook or journal on the subject),  “Carbohydrates are a common source of energy in living organisms, however, no carbohydrate is an essential nutrient in humans.”

Limiting fats and proteins in our diets is actually detrimental to our health. Completely cutting out carbohydrates has no ill effects whatsoever.

A few of my friends are worried about my cardiovascular health. After maintaing a low-carb diet for nearly a year of my blood pressure, lipid profile and other markers have vastly improved and are now within the normal range. There are a few journal articles that show a 28% increase efficiency when cardiac muscle is running on ketones from metabolizing fat. Here’s one:

The fundamental reason why the metabolism of ketone bodies produce an increase of 28% in the hydraulic efficiency of heart compared with a heart metabolizing glucose alone is that there is an inherently higher heat of combustion in Image-β-hydroxybutyrate [a ketone] than in pyruvate, the mitochondrial substrate which is the end product of glycolysis. (Emphasis mine.

The author of the Johns Hopkins study mentioned in the Times article shared his experience after three years of carb restricted dieting.

Dr. Stewart also has amassed some intimate anecdotal evidence. For a small pilot study several years ago, he became a test subject, adopting a low-carbohydrate diet and regular exercise routine. For three years, he has maintained both the diet and the workouts. He is 40 pounds lighter these days and, he said, continues to ace tests of his blood-vessel health.


I’m down 4.6 pounds in 5 days.  Not too shabby considering I was out of town 2 of those days.  Reference Timothy Ferriss in 4 Hour Body, “Having followed this diet in 30+ countries, I can state without exception that travel is not a legitimate excuse for breaking the rules.”

I took a bag of almonds with me and ate those instead of the “fruit” bar and crackers they were handing out on the plane.

When I ate at restaurants I asked for substitutions.  I didn’t even mess with the breakfast potatoes –   I figured if they were on my plate I’d eat them.  So I asked for veggies instead.  The waitress initially said they didn’t have any vegetables – but I asked for the ones they had listed in the veggie omelet and said I’d pay extra.  Suddenly it wasn’t a problem.

Ferriss refers to the extra $1 to $3 we pay for substitutions as a sixpack tax.  I’m no where close to a sixpack, but I’ll happily pay $1 for veg if it means I’m down 4.6.


25.4 to go / 55 days

60 to 30 by 30

Its been a long, long time since my last post.   I’ve gained 20 plus pounds.  And that’s not just because I fell and broke my coccyx.  Nope.  That happened in November and now its March.  I’ll tell you a little secret: I’ve gained weight because I haven’t had any exercise and I’m eating more.  Whats worse, I’m eating all that bad stuff like sugar and carbs.

So, here we are.  I’ll be 30 years old in 60 days.  I’m sort of OK with that, but I’d be much happier if I was 30 and a lot lighter.  I’m actually going to officially try for 30 pounds by 30 — I like the ring of it.   60 days to 30 pounds down by my 30th birthday.  And truth be told I need to lose about 75 pounds.  For all you 2 pound a week folks, I realize I’ve waited until just 2 months before the big date.  The math on that is 3.75 pounds per week.  I know its a little extreme – but hey!  Lets try our best and see where we end up.  If I hit 20 pounds I’m still winning!

I’m starting off today by going to spinning.  Its an old favorite of mine, and its a great one for burning calories.  I think whilst at the gym (for the first time since the summer) I’ll also do a few reps for my arms.

In terms of diet, I’ll be following the beloved Atkins.  I’ve also been reading the 4 hour body.  I think the trade there is bacon for beans, but I do like the one day a week cheat so I may lean more towards that.

Wish me luck.  I’ll keep you posted!

Being Cold Burns Fat

Here’s another pearl of wisdom from Four Hour Body by Tim Ferris.

Men acutely exposed to cold for two hours (in a liquid-conditioned suit perfused with 10°C [50°F] water) have been observed to increase heat production by 2.6-fold and increase the oxidation rate of plasma glucose by 138%, of muscle glycogen by 109%, and of lipids by 376%. Raising the body’s heat in response to cold exposure is done mostly by burning lipids (50%), then glycogen from muscles (30%), then blood glucose and proteins (10% each).

Burning 376% more fat by being a bit cold seems like a good trade off. Continue reading “Being Cold Burns Fat”

Can I have My Gym Back

It’s Friday, seven whole days into two thousand eleven. The  Fitness Factory was still filled with new faces in fancy new workout clothes loping along on the treadmills reading Men’s Health and Cosmo.

The New Years Resolution to lose weight is probably a good one. Even if you haven’t joined the gym or started eating healthy foods you can still tell yourself that you’re waiting until the newbies thin out and eventually go back to their lackadaisical lifestyles. If you’ve joined several gyms for several Januarys and lost motivation try something easier and much cheaper. The Kettlebell swing.

Continue reading “Can I have My Gym Back”