POSTED ON 1 JULY 2011 BY BRODRICK KENT

Myriads of dieters on their quest to be slim and who seek nutritional truth, remain confused and cautious about the degree of carbohydrates they should include into their menu. Fruit contains too much sugar. Can I eat bread? Don’t eat pasta, it’s fattening!

The perception that many hold true; is that the consumption of carbohydrates elicits the release of insulin (true), insulin then ushers glucose from carbohydrates into the cells (true), where these sugars become fat (false). These are just some of the misconceptions that have widely been accepted as nutritional law and the reason why so many chronic dieters continue to battle the bulge. 

Fuelling these false impressions are authors of popular diet books who inaccurately vilify carbohydrates, condemning them as the primary cause of weight problems. There are several issues with this assumption. The first one being that all populations who consume starch-based diets, that is wholegrain rice, pasta, noodles, beans, fruit and vegetables; remain thin, robust and healthy. Secondly, the carbohydrates found in potatoes, pasta and oatmeal are simply long chains of natural sugars that provide energy for the body. Some are absorbed slowly and others more quickly. Your brain solely runs on these molecules, as well as every energy producing cell in our body. Finally, fat contains twice as many calories per gram as carbohydrates do. Before we review some starch stuffing experiments, it would be helpful to understand our nutritional needs from a structural and genetic perspective.

A Structural Comparative of Eating

The fundamental reason we eat, is to provide ourselves with the energy to run our bodies.  The digestive process begins in our mouth, thanks to our saliva. Humans posses an enzyme on our tongue called amylase, whose sole purpose is to seek out and digest carbohydrates. Different plants contain varying concentrations of starchy sugars that we are innately tuned to seek. Root vegetables, green vegetables, beans, whole grains such as, rice, barely, corn, oats, legumes and fresh fruit are just some examples. Amylase doesn’t drive us to seek out amino acids or raw fat. 

In fact, there is no starch in meat, chicken and eggs. For this reason, the thought of chewing on a big raw bloody steak isn’t so appetizing for most people, nor is the thought of gargling down 6 raw eggs for breakfast. Culture, custom and habit has introduced many dietary behaviors that may be common practice, but not necessarily natural for humans. True flesh eating animals don’t cook their catch and/or separate prime cuts from eyes, tendons, bone, feathers, fur or intestines. However, we humans have to cook, add salt and sauces to these foods to make them palatable. 

Not only would it be impractical for us to chow down, with our flat blunt teeth and flimsy fingers, on a dead animal, but the thought of eating uncooked rotting flesh doesn’t come naturally for humans and is quite repulsive. However, this is second nature for animals who innately stalk their prey, who boast daggering teeth, produce acidic salvia and who are structurally designed to tear apart and devour large quantities of animal flesh. Furthermore, when meat eating animals consume animal flesh they release ten times the amount of hydrochloric acid in their stomach, compared to humans, which creates the perfect environment to digest rotting flesh. Whereas, humans are alkaline beings, whose stomachs prepare itself for complex sugars, fibre and a healthy mixture of micronutrients. 

Our innate drive to consume starchy foods not only provides us with complex and simple sugars to run our bodies, but carbohydrate containing foods also deliver a broad symphony of nutrients and other food factors required for maintaining a healthy body. With starches comes packed healthy amounts of amino acids, which are sent to repair worn tissue.1 We also acquire healthy amounts of fats, vitamins, minerals, alkalining substances that promote ideal acid/alkaline balance and blood health, cancer fighting phytonutrients and antioxidants that protect us against oxidative stress or premature aging. 

Another important food factor found only in vegetation is dietary fibre. Unlike carnivores who have very short intestines, and who are able to pass rotting animal flesh and eliminate cholesterol with ease; humans have extremely long intestines, perfectly designed for a high fibre diet. Aside from curbing your hunger and keeping you regular, fibre binds to toxins and hormones such as estrogen eliminating them in the faeces before they re-enter the bloodstream through the large intestine, ultimately causing trouble. Animal foods are high in cholesterol and fat, contain zero fibre, zero starch, are void of essential vitamins-folate, carotenoids, contain no phytonutrients and when metabolised these foods are highly acid forming. Chronic blood acidosis creates the ideal environment in your blood and tissue for the pathogenesis of several conditions such as, kidney stones,2 and osteoporosis.3

The take home message here is this: In some cultures it is normal to eat dogs and cats, while here they are our best friends. In France they serve horse, yet horses have been man’s right hand in the West for centuries. Some cultures consume meat and dairy, while others don’t. Humans are creatures of habit and much of what we do in terms of our diet and lifestyles habits are learned behaviours. We can drink, smoke, take illicit drugs, but just because we can do something, doesn’t make it right or consistent with our biological needs. Whilst it is clear that humans are ‘behavioral omnivores’ structural analysis4 and the larger body of scientific evidence suggests that humans are anatomically designed to thrive on a diet based on starches, fresh fruits, beans, vegetables and whole grains. As you read on you will see that under normal conditions carbohydrates are no more fattening than a glass of water. So the question remains, are carbohydrates fattening or do they hang out in bad company?

Carbohydrate metabolism

Carbohydrate molecules vary in their structure from one plant to the next. Beans for example contain resistant starch that is a densely packed molecule, which simply means, they digest very slowly. Whereas, fruits generally contain more loosely pack sugar molecules and digest more rapidly (although fruit sugars don’t elicit the release of insulin5). However, they all contain one distinct feature, that is, if you eat more than you need, your body doesn’t store the excess glucose as fat. Your body sends the extra glucose to build a more high-energy molecule called glycogen. Glycogen is like a battery reserve and we pack about 300g into our muscle and liver. Our body calls upon these reserves as our blood sugars dwindle throughout the day and more so with increased physical activity, such as exercise. There is another notable feature that results from this important function. Once our energy needs are met and our glycogen batteries are charged, excess glucose does not then turn to fat, instead, it is released as body heat. Researchers call this the thermic effect of food or TEF. 

Starch stuffing experiments  

Several researchers have attempted to test the theory that complex and simple sugars may make the costly conversion to fat. Swiss researchers stuffed participants full of simple sugars such as jam, sugared fruit juice and more complex starches from bread. This was about 480g in one meal and is nearly 2000 calories of food! The authors found that none of the extra calories had turned to fat. Glycogen stores were restored and the rest was dispelled as body heat.6 In another study researchers fed young men a diet that comprised of 80% carbohydrates, 9% fat and 11% protein for several days to ensure that their glycogen stores were recharged. They were then fed large quantities of carbohydrates - 2000 calories worth. Assessments over the next 24 hours showed no increase in body fat.7 What does this tell us? Even people who are following a high carbohydrate diet, gain no body fat by over consuming starches. 

Important note: If an individual doesn’t listen to their satiety signals (i.e. how full they feel) and continually overeats day in, day out, it doesn't matter what kind of foods you eat, you will gain weight. However, excess calories from carbs will make many other conversions before fat building becomes an option. Furthermore, if this conversion is forced to occur, a quarter of the excess calories are burned off attempting to convert sugars to fat, as it is a costly process. However, under normal conditions researchers simply can’t make this happen.

Fat building enzyme

Researchers studying chromosomes have discovered the gene responsible for fat storage. Lipoprotein lipase or better known as LPL is an enzyme whose sole purpose is to extract fat particles directly out of the bloodstream and will either stuff them directly into fat cells on your chin, hips, bum and thighs, alternatively, LPL will take the fat particles and drop them into your muscle cells to use for fuel.8 If the bodies energy needs are met from adequate blood sugars, LPL proceeds with fat storage only. LPL is not looking for amino acids or for carbohydrates, only fat. One exciting fact from this discovery is, if you don’t provide LPL with the raw material for fat storage, it won’t build fat. We need some fat, however, despite what food companies would have us believe, human fat requirements are very low, about 3-4% of calories and shouldn’t exceed more than 10-15%. This amount is consistent with recommendations set by world health authorities 9 and heart healthy populations.10,11,12

Historically, LPL’s job has been a modest one, liberating the healthy amounts of fat from a diverse range of fruits and starchy vegetables. However, today LPL is bombarded with food-fats such as animal fat and vegetable oils. Not only are these predominately the wrong kinds of fats but this amount of fat well and truly exceeds our biological needs and only adds a whole heap of unnecessary calories for LPL to stuff into obvious places13 (x1 table spoon of oil, of any description, contains 120 calories).

Fat makes you FAT!

Fat contains 9 calories per gram, that’s more than twice the amount of calories found in 1 gram of carbohydrate. Our bodies strongly prefer not to convert sugars to fat, whereas, fat goes from your lips to your hips without even making one biochemical conversion. Yes, that’s correct. It doesn’t change its structure one little bit, effectively, making for quick, easy storage. How do we know this? Fat biopsies taken from the behinds of willing participants show that the fat molecules are specifically from chicken, pork and other food fats and not the ‘sugars’ from cakes, cookies or mars bars. Researchers cannot only see what someone has eaten for dinner earlier that week, they can tell what was on your plate years prior.14,15 

Carbohydrates continually get a bad wrap, but if you take a closer look you will see that many carbohydrate containing foods rub shoulders with one big fat social deviate. Is it the pasta that is fattening, or the meat sauce and olive oil invited to the same party? A small serve of mashed potatoes may contain around 70 calories, but, add one table spoon of oil or fat and you have almost doubled the caloric content of the food, without adding any bulk to the dish. Meaning, butter and oils are concentrated fat and calories that only add unnecessary calories to the meal, while having no impact on blunting your hunger drive. In fact, food scientists combine fat and sugars in foods for one reason, it stimulates an individual to eat more. Raw sugar by itself doesn’t stimulate the brains pleasure centre, like fat and sugar combined.16 

The take home message: Our bodies want to perform the most efficient function possible. When we consume carbohydrate containing foods with added food fats, our bodies use the glucose from carbohydrates first and foremost for energy. Excess glucose is sent to recharge the high-energy molecule glycogen and then let off some heat. The food fats that accompanied the meal are effortlessly escorted by your fat building enzymes, to fat storage. The amount of fats found in unrefined vegetation is consistent with our biological needs. Adding food fats, in the form, of vegetable oils and animal fats, easily exceeds our bodies requirements, compromising cardiovascular health and only adding to an ever expanding waistline. 

Stop chewing the fat and boost your metabolism

Insulin is a hormone released by the pancreas in response to eating food. Its job is to escort glucose, amino acids and micronutrients through the bloodstream and into the cells. The idea is that, starches are broken down in the stomach and sugar molecules are steadily released incrementally into the blood. This stimulates the pancreas to release insulin. Insulin then acts like a key, opening the cell walls and allowing whatever nutrients are needed to enter. This process momentarily stops fat metabolism, because theoretically, your body has obtained sufficient energy in the meal just consumed. Under normal conditions the cessation of fat burning is brief. However, certain dietary factors can interrupt this function, leading to insulin insensitivity and turning off your fat burning machinery more effectively than it should. 

1. Many people today are consuming carbohydrate rich foods that have had the fibre content mechanically stripped. Fibre is very important because it naturally acts to dilute the amount of calories in untampered plant foods by adding noncaloric volume, filling you up before you exceed your energy needs. Another important role of fibre is it releases glucose into your blood at a slow and steady rate and insulin is released accordingly. When sugars are absorbed at a more rapid rate, the pancreas overcompensates sending out more than normal amounts of insulin to deal with the influx of sugars. In an act of efficiency, insulin then swiftly takes these sugars from the blood, stuffing them into the cells and leaving you with low blood sugar. This results in a rapid rise and fall in energy, triggering food cravings and mood swings not long after eating.

2. Have you ever noticed what ocean water looks like after an oil tanker spills its load? It becomes all thick and gooey, obstructing normal life. The fish, sea birds and wild life can’t function optimally and die. Similarly, when unnatural amounts of food fats from animal products and vegetable oils enter our blood - increasing viscosity (thickness) - the blood becomes like grease, diluting insulin and diminishing its ability to open the cells and deliver the much needed nutrients and energy. Consequently, leading to insulin insensitivity and high blood pressure,17 again resulting in a lack of energy and fatigue. Additionally, excess glucose accumulates in the blood, signaling the pancreas to send more insulin, over working the pancreas and placing pressure on your kidneys to excrete excesses. Your fat burning machinery is also made redundant, because your body wants to utilize the blood glucose first, reserving fats stores for future 'famine' (which today never happens).

3. Excess fat consumption also leads to an accumulation of intracellular fat, inside our muscle cells. This is not the same as the fat found on your bum and thighs. Each cell contains a thin layer of this intracellular fat or intra-myo-cellular lipid, that your body keeps on hand for quick access for energy. Due to excess fat consumption and the bodies preference for glucose metabolism over fat metabolism, the cells become clogged with excess fat, obstructing glucose - amplifying the issues above - resulting in insulin resistance.

Breakthroughs in current diabetes research shows that this is the genesis of type 2 diabetes, commonly thought to be a carbohydrate dysfunction.18 This misunderstanding has lead some industry groups to naively promote the use of high protein diets to treat diabetes, under the assumption that protein, unlike carbohydrates, doesn’t stimulate the release of insulin (a favourable outcome for diabetics). However, research shows that animal protein has greater effect on insulin response than carbohydrates do.19 Additionally, diets heavy on protein are not consistent with long-term health outcomes.20,21 When researchers placed diabetic test subjects on high fibre, carbohydrate rich diet that excluded animal fat and vegetable oils, insulin sensitivity was restored and three quarters of the participants were able to discontinue their medication, reversing their condition.22

Summary

The consumption of excess fat and calories are responsible for weight problems, not carbohydrates. For stable weight loss, rather than focusing on how much you eat, focus on what you eat. Participants following a low fat carbohydrate rich diet lost their desired weight with no calorie restriction, eating as much food as they liked.23 It would be important to choose the type of carbohydrates you consume more wisely, predominately eating high fibre beans, fruits, legumes, vegetables and whole grains. However, the issue regarding weight gain, are those calorie dense food fats that come tightly packaged with most tampered carbohydrates and in high concentration in vegetable oils and animal products. These should be excluded until an individual reaches their ideal weight. How long this takes will depend on how much weight you have to lose.

Once this has occurred and insulin sensitivity is restored, vegetable oils should be used sparingly, if any. The inclusion of organic/non-organic animal foods - of any description - should not consist of anymore than 2-3 serves per week. If the consumption of food fats and animal protein exceed this threshold, you will significantly increases your risk of developing heart disease, cancer, a reoccurrence of weight problems and other issues associated with dietary excess.24,25

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