The carb myth part 1: Why “fat-free” can still make you fat

Ah, the 1980s and early 1990s, the era of ultra-low-fat diets. We were told that we could eat anything we want, as long as it didn’t have fat in it. Calories were irrelevant! Just purge the fat and you can eat everything with impunity! I don’t know about you folks, but I chowed down a whole lot of plain rice and brownies made with applesauce. My boyfriend, now my husband and the son of two fantastic chefs (and a pretty adept guy in the kitchen himself), suffered (mostly) in silence through flavourless steamed veggies, leaden baked goods, and my fat fascism, though he did try to sneak bacon and butter into things occasionally.

Well, at the end of it all in early 1997, I was still overweight. Desperately, I tried to purge every last living fat molecule from my life. I sautéed veggies in water. I ate pasta with plain tomato sauce.

I hovered over my husband when he cooked, making sure he didn’t try to infringe on my fat-free life with an extra blop of cooking oil. I even tried going vegetarian, but had to quit that after a couple of weeks when my tummy growled constantly with hunger. And through it all, I happily scarfed “fat-free” treats: Snackwells, hard candies, Jello, gelatos and sorbets, fat-free salad dressings with a weird chemical aftertaste…

Are you doing the math by now, dear reader? It wasn’t the fat in my diet that was the problem, it was the carbohydrate intake. In other words, I had replaced some negligible fat calories with tons of sugar and starch calories.

When I discovered weight training, I discovered that bodybuilders ate strangely. They ate lots of lean protein, avoided simple sugar and starch carbs like white bread, pasta, and white rice, and (gasp!) deliberately ate fat! I thought they were all insane. I began training, but kept eating my fat-free, high-carb diet. I was doing OK in the gym thanks to beginner gains, but I sure wasn’t losing any fat. I started to think I was destined to be heavy. Most of the women in my family are “pleasingly plump”. I figured it was genetics. I figured I was a lost cause. I got pretty depressed about the prospect. Then my training guru told me I wasn’t eating enough protein, and suggested supplementing with flax seed oil. I thought it was the craziest thing I’d ever heard. Eat fat on purpose?! But, after a few weeks of him nagging me to do it, I gave in and bought my first bottle of flax seed oil. (by the way, you can read more about why you shouldn’t drop your fat intake when dieting, and about flax seed oil here). And I started cutting back on plain pasta in favour of lean protein. With almost no other effort on my part besides regular visits to the gym, the fat began dropping off.

So, what was the reason for this transformation? Why is a diet low in carbs conducive to losing fat? Let’s start with an explanation of why simple carbs (sugars and starches) have more of a role to play in fat deposition than dietary fat.

Carbohydrates are one of the three main groups of macronutrients in the diet (the other two are fat and protein). In the carb group are various kinds of sugars such as sucrose (table sugar), fructose (fruit sugar), lactose (in milk), and so forth, as well as various kinds of starches, which are composed of sugar molecules bonded together. Our bodies use glucose, one of the very simplest sugar molecules, as a main source of fuel.

The closer something is to glucose, the more quickly it is digested and used as fuel. Simple sugars are very easily digested and converted to glucose. Starches are somewhat harder for the body to convert to glucose, so it has to expend a bit more effort doing so. Refined starches such as white flour, white rice, cornstarch, and products such as breakfast cereals, white bread, and pasta made with these refined starches, are easier for the body to convert to glucose than starches from whole grains (barley, oatmeal) and vegetables (except for potatoes and yams). Because more complex carbs such as whole grains and vegetables contain more fibre, they are not as readily broken down by the body, and so do not as quickly become glucose. (By the way, fructose is not converted in the same way as glucose. Thus some people claim that substances such as high-fructose corn syrup are actually “good” for you, because they don’t raise glucose levels rapidly. This is BS. Sugar is sugar is sugar.)

In addition, complex carbs contain other things like vitamins and minerals which are often missing in refined carbs because of their extensive processing. Have you ever noticed that white breads trumpet how vitamin- and mineral-enriched they are? Did you ever wonder why breadmakers had to put those things back into the product? It’s because they took them out in the first place!

OK, so why is it important to think about how quickly foods get converted to glucose? For one thing, the human body is a very thrifty machine. It constantly worries that we may encounter a time when we do not have enough to eat, so it socks fuel away for a rainy (or hungry) day. This was a great idea when we were running around trying not to get et by sabre-toothed tigers while scavenging for edible roots, but not as brilliant for our modern industrialized lifestyles where food is as close as a quick stumble to the fridge. It’s the reason why starvation is a really long, drawn-out death: the body has quite extensive resources to deal with food shortages.

When we have an excess of glucose gushing into our bloodstream, as happens with the consumption of simple and refined carbs, our body handles it in two ways. One way is to excrete glucose through the urine, though this is only used if the body cannot deal with the excess glucose, as in the case of diabetics. In most people, the body’s main technique is to store excess glucose as fat. Let me repeat that in case you didn’t catch it. It stores excess sugar as fat. Are you making the connection now? It’s probably not the fat in your diet that’s making you fat, it’s more likely the sugar.

When metabolizing glucose, the body releases insulin from the pancreas. Insulin causes the glucose to move into the cells so that it may be processed. If the cells don’t need all that glucose for their various functions, then they convert the glucose to triglycerides (fats), and store the fat within the cells, organs, or in adipose (fat) tissue. In the process of sending the fat molecules to their destination (mostly adipose tissue), the fat molecules are moved through the bloodstream. You end up with fat roaming around in your blood, which (along with the inflammatory cascade precipitated by abundant blood sugar) eventually spells cardiovascular problems, such as heart disease and stroke, as well as an eventual increase in bodyfat. “Bad” fats made from sugars can also interfere with “good” fats such as those from flax seed oils, which prevents the “good” fats from doing their job.

But the diabolical work of simple and refined sugars doesn’t end there. These kinds of carbs, as I said, are digested very quickly. There is a rush of glucose into the body’s systems. The body responds by releasing insulin, which because it shoves the glucose into the cells, results in a blood sugar drop. Many refer to this quick blood sugar rush and resulting drop as an “insulin spike” (a friend of mine refers to a particular kind of sugar-saturated donut as “The Insulin Whiplash”). It’s like a sugar rollercoaster. People who are sensitive to this may feel shaky, fatigued, dizzy, faint, and/or sleepy after consuming these kinds of carbs in significant amounts. More extreme symptoms of hypoglycemia (low blood sugar) include depression, mood swings, and even unconsciousness. A chocolate bar may give you quick energy with the flood of glucose into your system, but your energy levels will drop through the floor 30 minutes or so later. And here is where the vicious cycle completes itself: you’re left craving more simple and refined carbs. It’s like a nutritional perpetual motion machine. Eat more simple carbs, desire more simple carbs. Which, of course, spells F-A-T.

It’s ironic that our problems with sugar are largely a result of industrialization and class snobbishness. It used to be that the refinement of foods was something that only the middle and upper classes could afford. Only peasants ate dark whole grain breads and picked their food from the fields. Milady and milud did not soil their digestive systems with such low-class things! Maybe a better diet was the working-class revenge which Marx envisioned! Now many kinds of good-for-you foods are classified as “health foods” and only the privileged can afford to buy them at specialty shops, while refined foods like white bread and Twinkies are some of the cheapest foods one can buy.

Does all of this mean that sugar is the enemy? Well, yes and no. Yes, we should be very conscious of our simple and refined carb intake when trying to lose fat. But if we make informed food choices, then carbs are relegated to their proper place of reliable energy source. How can we do this?

Choose fibrous, complex carbs over simple, refined carbs. So, eat brown rice instead of white, and whole wheat pasta instead of regular pasta. And if you can, cut back on the sugar you put into your coffee. Two spoonfuls of sugar, twice a day, add up to a lot of extra carbs over a long time. Combined with caffeine’s tendency to drop your blood sugar, and you have hypoglycemia city.

Change the way you structure your meals. It used to be that a healthy meal had some protein (usually as meat), some starch (potatoes, rice, pasta, etc.), and some veggies on the side. I suggest getting rid of the starch altogether and increasing the portions of lean protein and veggies. For example, one of the things I love to do is make a big salad with all kinds of veggies (and sometimes even fruit and/or nuts and seeds), and toss some chopped cooked chicken or steak into it. Or, I make curries with chopped chicken or beef, some chopped veggies, and maybe some chickpeas. Instead of a tuna sandwich on bread, I throw some tuna in a bowl and mix it with some mayo, chopped tomatoes and green peppers, and maybe some sunflower seeds. You’re only limited by your creativity.

Eat more regularly. If you eat two or three times a day, it means that your blood sugar undergoes more fluctuations, which can mean less energy and more readily deposited bodyfat. If, on the other hand, you eat five or six small meals a day, and these meals have some protein and fat in them (in other words, I don’t mean that a meal is a handful of fig newtons!), then your blood sugar remains more constant, you’ll have fewer cravings, more energy, and generally feel better. Plus your metabolism will keep revving because your body has to expend the effort to digest stuff more frequently.

Learn to read labels to look for hidden sources of sugar. Soft drinks and fruit juices are loaded with sugar. If you must drink pop, at least switch to diet (and this is a temporary solution; try switching to soda water instead of consuming all the chemicals in diet pop). Other serious sources of sugar are pastries (cookies, pies, Twinkies, etc.), candy, many processed and canned foods such as sauces (ketchup, peanut butter, syrups of all kinds), juices, and fruits, and dairy products such as flavoured yogurts or ice cream. Most breakfast cereals are pure junk from a simple carb standpoint. They might as well call Cheerios “Gluc-Os”. You’d be amazed at what contains simple and refined carbs, so read the labels on everything!!

Finally, and this is a corollary of the first thing, learn about the glycemic index. The glycemic index (GI) is a representation of how readily foods are converted to glucose in your body. So, simple and refined sugars have the highest GI, while fibrous, fat- or protein-rich foods have much lower GIs. The body has to work harder to convert more complex carbs, protein, and fat to glucose. Choosing foods that have lower GIs will help prevent the dreaded “insulin whiplash” since their slower conversion means less of a glucose rush. It’s not a perfect list — again, fructose appears to have a low GI, for example. But it does correlate decently well to which foods are whole foods, and which foods are highly processed, low-fibre foods.

In conclusion, just because something is “fat-free” may not mean it’s good for you. “Fat-free” foods are often very high in simple and refined carbs, which means that in your body, they’re as far from “fat-free” as you can get.