Secret 31 is an alphabet soup of biochemistry and undesirable conditions such as hypoglycemia, hyperinsulinemia, glycation, advanced glycosylation, insulin resistance, DHEA, adult-onset diabetes, eicosanoids, glycemic index, glycemic load and atherosclerosis (as predicted by the afore-mentioned hyperinsulinemia). To put it simply, Secret 31 takes a closer look at carbohydrates, classifies them by their glycemic index and advises against a high GI diet.
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| Off the glycemic index scale |
What is GI or glycemic index? This index, which was invented in the early 1980ies by researchers at the University of Toronto, measures how quickly a carbohydrate releases glucose into the bloodstream. Two systems of measurement exist: the standard method equates glucose to 100, a less popular one equates white bread to 100 (and then glucose would be around 125). High GI foods have a GI above 70 on the standard index and include cereals, white bread, white rice, cakes, cookies, pop and sweets. Medium GI foods or those with a GI between 56 and 69 include basmati rice, whole wheat products, sweet potatoes (an Okinawan favorite), baked potatoes and pasta. Low GI foods have a GI of 55 or less and include most fruits and nearly all vegetables. Since meat and diary products are low in carbohydrates, their GI would be on the low end of the scale. Low GI carbohydrates take longer to digested and release glucose more gradually into the blood. In general, you want to avoid a diet of high GI foods as the constant blood sugar spikes can, over time, lead to hyperinsulinemia and adult-onset diabetes. The spikes are caused by the quick release and absorption of glucose which, in turn, leads to further sugar cravings. You can reduce the GI of high GI foods by mixing them with foods low in GI i.e. a white baguette with cheese, or rice with fish and vegetables. Sometimes reaching for a high GI food is necessary, for example after intense exercise or if you are hypoglycemic (have low blood sugar) as your body needs to obtain energy quickly. However, most of the time a low to medium GI diet will provide plenty of energy. Note that the glycemic index applies to foods that yield about 50 g of available carbohydrate when consumed, thus the GI does not qualify the proteins and fats in your diet. Also note that foods that are not necessarily considered healthy, such as ice cream and chocolate cake have a low glycemic index due to their high fat content (38 and 37 respectively). In fact, many countries, despite having staple diet of high glycemic foods such as potatoes and rice, actually have a low incidence of diabetes. If you would like to find out more about GI, Sally Beare recommends Jack Challem's "Syndrome X". A more scientifically accurate book is Reaven's "Syndrome X: The Silent Killer". While GI may be useful to ascertain how quickly you can access glucose in a carbohydrate, this is not the optimal guide to choosing healthy food. Diets such as the South Beach diet use GI values.
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| Maybe it is not the high GI value, but the presence of artificial flavors, colors and trans fats that are pose health hazards? A more useful measure of the impact of a carbohydrate on your system is the glycemic load. In contrast to the glycemic index, the glycemic load also takes into account the amount of carbohydrate consumed. GL = GI x the amount of available carbohydrate in a 100g serving, in other words GL is a weighted GI value. For example watermelon has a high GI value (over 70), but since watermelon consists mainly of water and contains very little carbohydrate, its GL is low (5). Also watermelon provides invaluable lycopene. If you avoid watermelon based on the GI, you are inadvertently denying yourself a wonderful source of lycopene. On the other hand the GL of white rice or a baguette is high (above 20). But who eats a plain bowl of race or a 'naked' baguette? White rice tends to be eaten with fish or meat or tofu and vegetables, baguette with butter, cheese, or ham, so the overall glycemic load is lower and does not cause unhealthy sugar spikes (baguette with only honey and without butter would have a high GI!). |
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| Low GI and low GL. More importantly - delicious! |
Now that we have investigated GI and GL, let's explore some of the ailments Sally Beare mentions in Secret 31 and find ways to avoid them:
Hyperinsulinemia: a condition whereby excess levels of insulin circulate in the blood. It is also known as 'pre-diabetes', insulin resistance or Syndrome X. Recommended treatment includes exercise, reducing simple sugars, processed carbohydrates, potatoes and white bread and eating more vegetables and legumes.
Insulin resistance: a condition whereby insulin becomes less capable of reducing blood glucose. Obesity exacerbates this condition, especially visceral adiposity (fat around the mid-riff). Possible bad effects of a high-fat diet can be moderated by fish oil or other sources of omega-3 fatty acids. Despite a diet high in fats, Alaskan Eskimos have a low level of IR due to the presence of large quantities of fish oil in their diet. Habitual and excessive consumption of carbohydrates can lead to IR and studies have shown that trans fats are extremely deleterious. Alaskan Eskimos who switch from their ancestral diet to the Standard American diet exhibit the same Western diseases as the rest of the U.S. Exercise and weight loss are the first line of treatment.
Adult-onset diabetes or diabetes mellitus type 2: a metabolic condition with abnormally high blood glucose. In the U.S., 8% of the population is diagnosed with this condition. Helpful are exercise, dietary change such as increasing dietary fiber and reducing the consumption of trans fatty acids. Obesity, especially intra-abdominal fat, and smoking exacerbate the condition. Long-term complications include heart attacks, strokes, amputations, failing eye sight, kidney failure and testosterone deficiency in men.
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| Universal symbol for diabetes |
Atherosclerosis: a gradual and imperceptible hardening of the arteries that can suddenly result in a catastrophic blockage of an artery and cause a heart attack or stroke. Atherosclerosis is caused by an inflammatory reaction of the cell walls to retained low-density lipoproteins (LDLs). Inflammation, rather than fat or cholesterol is the cause of atherosclerosis. Once in the wall, LDLs may be oxidized by free radicals and become toxic. It is surmised that atherosclerosis is a vitamin C-deficiency disease. Vitamin C ensures a strong and flexible vascular system. Trans fats also play a harmful role. In one study rabbits were fed heated soy bean oil (I assume GMO soybean) and displayed "grossly induced atherosclerosis and marked liver damage". Most of the oils sold in U.S. supermarkets are refined, bleached, deodorized, and gummed thereby making it much harder to detect rancid and thus harmful oils. Exercise, loosing weight and not smoking help forestall atherosclerosis. Since cholesterol is an integral part of cell membranes and more than 80% is manufactured by the body, reducing dietary cholesterol has little effect. A lower external supply only makes the body create more cholesterol internally. More effective than changing the amount dietary fat or cholesterol is reducing the intake of carbohydrates, especially simple carbohydrates and improving the quality of fat. Avoid trans fats and increase the intake of omega-3s. Also, avenanthramides, found in oats, have an anti-inflammatory effect and help prevent atherosclerosis (oats tend to be a good source of dietary fiber).
So, in a nutshell:
- maintain a healthy body weight
- avoid continual blood sugar spikes
- reduce the use of highly-refined oils (or most cheap non-expeller pressed vegetable oils)
- include fish oils or other sources of omega-3 fats in your diet
- avoid trans fats
- enjoy the occasional dessert but do not make this a habitual part of your nutrition
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| Everything in moderation Enjoy! |
Afterthought: carrots originally were classified as having a high glycemic value. Further studies, however, have reclassified carrots as having a low glycemic value. If you come across a book that categorizes carrots as being high on the GI, then you are probably looking at old data.
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