The PCOS Plan. Jason Fung
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test and an internal ultrasound confirmed she was five weeks pregnant and all was well! Low-carb works. Insulin resistance is reversible.
I encouraged Gabi to stick with her low-carbohydrate diet during pregnancy to prevent gestational diabetes, knowing that women with PCOS are more prone to this and other gestational conditions. She and the baby remained healthy and well throughout the pregnancy, and Beautiful Banting Baby was born in October 2017.
What We Know about Obesity
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THE WORLD HEALTH Organization defines obesity as a state of “abnormal or excessive fat accumulation.” Today, it is a worldwide epidemic affecting all ages, genders, and ethnicities, and it’s worsening with each successive generation. My 93-year-old grandmother never met an obese person until recently. She knew of no overweight kids in her school, family, or social circles. My 60-year-old mother had almost no overweight classmates. When I went to school, I had a few overweight classmates. They weren’t unusual, but they weren’t common either. My children, however, have many overweight and even obese little buddies.
Worldwide, obesity has nearly tripled since 1975. By absolute numbers, the United States is the most obese country in the world, followed closely by China and India. By proportion of population, 50.8 percent of the Cook Islands in Oceania is obese, followed by Qatar at 42.3 percent and the United States at 33.7 percent, according to a 2017 report of obesity rates by country.1
Obesity is commonly classified by the Body Mass Index (BMI), which compares weight to height but ignores factors such as muscle mass, age, and fat distribution. This definition limits the BMI’s overall accuracy, but it is generally a simple and useful measure.
Figure 4.1. Body Mass Index2
Ironically, the overriding concern of the 1970s was global hunger and the difficulty of increasing food production to avoid mass worldwide starvation. Yet, today we live with a global obesity epidemic that kills more people than does starvation. This slow-motion surge toward rampant obesity was completely unforeseen and has shocked most public health authorities. The resulting health consequences are dire. Having a BMI in the obese or extremely obese range is a risk factor for many serious health ailments, including PCOS, as well as the following:
•Heart disease
•Stroke
•Lung disease
•Diabetes
•Cancer
•Non-alcoholic fatty liver disease
•Gall bladder disease
•Osteoarthritis
•Pancreatitis
So how did this happen?
THE LINK BETWEEN DIET AND OBESITY
IN 1977 A U.S. Senate committee published a new set of dietary guidelines for Americans. Today, the U.S. Department of Health and Human Services and the U.S. Department of Agriculture (USDA) update and publish a new set every five years. To battle heart disease, which was the primary health concern in the 1970s, the guidelines recommended significant cuts to people’s consumption of dietary fat. Even as people became obese, these same guidelines were trotted out to do battle with this new enemy. The original 1980 food pyramid from the USDA suggested that Americans eat 6 to 11 servings of refined grains, such as bread, cereal, rice, and pasta every single day. I’m not sure that I know anybody who considers eating 11 slices of white bread daily to be a slimming diet. Yet this was the very diet recommended by the government of the United States and followed by other countries around the world. Virtually every health professional, doctor, and dietician in the world was soon giving this advice.
In addition to low-fat diets, the other big trend of the 1970s was the increase in leisure-time exercise. Before then, the idea of exercising for health or fun was as foreign as rap music to disco fans. Originally this advice was given to improve heart health, leading to a boom in “cardio” exercises such as aerobics and running. This advice was soon co-opted for weight loss as well, despite the utter lack of evidence supporting the efficacy of these exercise programs for weight loss.
Figure 4.2. The U.S. Department of Agriculture’s 1992 food pyramid3
Today, there are more gyms per capita than ever before. Local marathons and 10K races attract tens of thousands of runners. For most of her life, my grandmother never saw a gym. While exercise certainly has many health benefits (improved muscle tone, improved flexibility, increased bone mass, etc.), weight loss is not one of them. Scientific studies repeatedly confirm the minimal weight-loss effect of exercise programs. Two main reasons explain why. First, doing more exercise generally leads to eating more food, which will negate much of the weight-loss effects. They don’t say that you are “working up an appetite” for no reason. Second, doing more exercise reduces a person’s overall activity at other times of the day. For example, if you work a physically demanding job like construction for eight hours every day, then it is unlikely you will get home and decide to go on a 10K run just for fun. If you have been sitting in front of a computer all day, then that 10K run may sound quite appealing, but increasing leisure time exercise does not change total daily activity.
From the 1970s on, we have continued to believe that a low-fat diet combined with exercise will reduce weight and that people who are obese are just lacking in willpower. What we now know is that while what we eat does affect our weight, dietary fat is not the culprit. To understand why, we need to look at what happens to food when it enters the body.
DIGESTION: HOW THE BODY BREAKS DOWN FOOD
ALL FOODS ARE a combination of three major components called macronutrients:
1.Proteins
2.Dietary fats
3.Carbohydrates
In turn, each macronutrient is composed of smaller units or building blocks.
Proteins are chains of building blocks called amino acids. In the human body there are at least 20 amino acids, which can be combined to form thousands of different proteins. Nine amino acids are considered essential because the human body cannot synthesize them, which means they must be obtained through diet. If you don’t eat enough of these proteins, you will become malnourished. Food sources of protein include meats, poultry, and seafood; dairy milk, cheese, and yogurt; eggs; beans and legumes.
Dietary fats are molecules called triglycerides, which are composed of a glycerol backbone and three fatty acids. Certain types of fat are also considered essential and must be obtained through diet. These include the omega-3 and omega-6 fatty acids. Food sources of fats include oily fish; dairy milk, cheese, and yogurt; eggs; nuts and seeds; coconuts; avocados.
Carbohydrates are chains of sugars such as glucose, fructose, or lactose. Table sugar, called sucrose, is composed of one molecule of glucose linked to one molecule of fructose. Starches, like flour, are composed of long chains of glucose in the form of amylopectin or amylose. There are no essential carbohydrates. Food sources of carbohydrates include grains; fruits and vegetables; beans and legumes; energy drinks and alcohol.
Food also contains microscopic amounts of vitamins (A, B, C, D, E, K, etc.) and minerals (iron, copper, selenium, etc.), which are known as micronutrients.
Digestion is the process of breaking down macronutrients—proteins, dietary fats, and carbohydrates—into their smaller components for absorption by the body. The