Why do we get fat

Chapter 30 The Truth Emerges: The Essence of Healthy Weight Loss (2)
One problem is that when people (experts or not, including myself) decide to evaluate the relevant evidence for something, they tend to look at what they want to see.This is human nature, but this nature prevents us from discovering real conclusions.In order to reduce errors of judgment, the medical profession established an international body in the mid-20s to conduct unbiased evaluations of various medical literature. This body is called the Cochrane Collaboration (Cochrane Collaboration).Today, the Cochrane International Collaboration is widely regarded as the most reliable authority on whether some medical intervention—such as a particular diet, a certain surgery, a certain diagnostic technique, etc.—actually achieves the results doctors hope for one of the institutions.

In 2001, the Cochrane International Collaboration evaluated the effects of a low-fat diet.The evaluation traced back to the entire medical literature from the 20s, and found only 50 clinical cases supporting the idea that a low-fat diet can reduce the risk of heart disease.In fact, many experiments were originally conducted to study the effects of low-fat diets on other diseases such as breast cancer, high blood pressure, visceral polyps or gallstones.But the researchers who conducted these experiments also reported that the subjects also had heart disease or eventually died of heart disease, so the data from these studies can also be used to evaluate heart disease.Strictly speaking, such reports cannot be accepted.

The Cochrane International Collaboration concluded: "Despite decades of effort and random sampling of thousands of individuals, the effects of fat on cardiovascular morbidity and mortality are subject to constant revision. At present these are limited, rather than conclusive evidence."

Then the Cochrane International Collaboration conducted the most extensive and expensive diet tracking survey to date.The survey tracks the impact of fat on women's health. 49000 middle-aged women participated in the dietary survey, and the organization randomly selected 20000 of them to adopt a low-fat diet. They ate very little meat and a lot of vegetables, fresh fruits and whole grains. After 6 years, these women had reduced their total fat consumption by 25 percent and lowered their total and LDL cholesterol (albeit only slightly) less than the other 29000 women who could eat and drink as much as they wanted.However, their low-fat diet had no significant effect on heart disease, stroke, breast cancer, colorectal cancer, and crucial fat accumulation.To put it bluntly, eating less fat and filling in the gaps with fruits, vegetables and whole grains has no apparent benefit.

At first, pundits were confident about the benefits of a low-fat diet, as if it were a worthwhile gamble.But with the progress of the experimental investigation and the investment of funds, they did not get the desired results.So they added that the research must have some flaws, and the results were irrelevant.

That's the truth about fat.

The circle of logic for arguing that a low-fat diet protects the heart is that if a certain cholesterol-lowering drug prevents heart disease, then a certain diet that lowers cholesterol must also prevent heart disease, and a diet that raises cholesterol must be heart disease. the cause of the disease.And fat can increase total cholesterol and low-density lipoprotein cholesterol.Therefore, fat must cause heart disease, and a diet restricting saturated fatty acids must prevent heart disease.

However, this logic has several fatal flaws.First of all, the function of medicine and the function of diet are two completely different concepts.Changing the nutrients in your diet can have many effects throughout the body, as well as on heart disease risk factors.For example, the fact that a certain dietary fat is more likely to raise LDL cholesterol than sugar does not mean that this fat increases our risk of heart disease or is bad for our health. harmful.

Secondly, fat is related to heart disease, but it cannot be said that fat causes heart disease. This logic makes the mistake of "cause and effect" and "correlation".For example, drugs called statins lower cholesterol and also protect against heart disease.This fact does not mean that the drug prevents heart disease because it lowers cholesterol.And aspirin, which cures headaches and also protects against heart disease.But no one would argue that aspirin prevents heart disease because it cures headaches.

Let's start with fat.Fat is a risk factor for heart disease, and the higher the level of fat in your bloodstream, the more likely you are to develop heart disease.There is no doubt about it.But it's the sugar we eat, not the fat we eat, that raises blood fat levels.

If you replace the saturated fatty acids in your diet with sugar—for example, cornflakes, skim milk, and bananas instead of eggs and meat in your breakfast—your LDL cholesterol may go down while your fat goes up.Lowering low-density lipoprotein cholesterol may be a good thing, but this good thing will be offset by the bad thing of rising fat.

Low HDL cholesterol is also a risk factor for heart disease.People with low HDL cholesterol had a much higher risk of heart attack than those with high total or LDL cholesterol.For women, high-density lipoprotein levels can predict future heart disease risk.In fact, HDL is the only predictor of heart disease risk.When researchers measured the genes of extremely long-lived people (greater than 95 years old), they found a compelling gene that helps the body increase high-density lipoprotein levels.

When you replace fat in your diet with sugar, your HDL decreases, which indicates that you are more likely to develop heart disease, at least predicting your risk.Again, if you ditch scrambled eggs and meat for breakfast and opt for cornflakes, skim milk, and bananas, your "good" cholesterol will drop and your risk of heart disease will rise.Conversely, if you switch from cornflakes, skim milk and bananas to eggs and meat, your HDL cholesterol will rise and your risk of heart disease will decrease.

However, the advice we usually hear is that we can lose weight and increase our high-density lipoprotein through exercise.But it is rarely heard that we can also replace sugar with dietary fat and protein to achieve the same goal.Nutritionists and public health authorities who insist that we should eat a low-fat, high-carbohydrate diet to avoid heart disease have admitted on some occasions that a carbohydrate-rich diet lowers HDL cholesterol, which can lead to heart disease. The risk of disease increases.A recent article in the New England Journal of Medicine stated that HDL cholesterol is "a biomarker of dietary sugar content."In other words, if your HDL is high, you can bet you're eating less sugar; if your HDL is low, chances are you're eating a lot of sugar.

When we start noticing the link between HDL and heart disease, we'll know to eat these instead of fattening sugars like meat or eggs, or even butter.It is important to know that the fat in these high-protein, high-fat foods is not all saturated fatty acids, rather, the fat in these animal products is a mixture of saturated and unsaturated fatty acids, all of which contribute to our LDL cholesterol HDL cholesterol and high-density lipoprotein cholesterol have different effects.

Take lard, for example.For a long time, lard has been regarded as a "killer fat".Lard was heavily used in bakeries and fast food restaurants until nutritionists touted the dangers of animal fats for heart disease and were forced to replace it with artificial trans fats—now discovered by nutritionists It is no less harmful to heart disease than animal fat.

You can easily find the fat content and specific ingredients of lard, as well as most foods, if you go online.You'll find that nearly half of the fat in lard (47 percent) is monounsaturated fatty acids, widely considered "good" fats.Monounsaturated fatty acids can increase high-density lipoprotein cholesterol and reduce low-density lipoprotein cholesterol.According to doctors, both are good things. Ninety percent of these monounsaturated fatty acids are actually similar to the fatty acids in olive oil touted by adherents of the Mediterranean diet.Over 90% of lard fat is indeed saturated, but a third of that is the same stearic acid found in chocolate, which is now also considered a "good fat" because it boosts our density lipoprotein levels, but had no effect on low-density lipoproteins.It's a good thing and a neither-bad thing.The remaining fat, which accounts for about 40% of the total, is polyunsaturated fatty acids, which can lower low-density lipoprotein cholesterol and have no effect on high-density lipoprotein cholesterol.It's also a good thing and a neither-so-bad thing.

Overall, more than 70 percent of the fat in lard will improve your cholesterol profile.In other words, it's hard to believe that if you replaced the sugars in your diet with the same amount of lard, there would be significant health hazards.It can actually lower your risk of heart disease and may make you healthier.The same goes for animal products like red meat and eggs.Be aware, though, that butter is a bit different in that only half of the fat will improve your cholesterol profile, and the other half will raise your total cholesterol altogether.

In the past 10 years, researchers have done quite a lot of experiments to explore the advantages and disadvantages of diets that are low in sugar, but high in fat and protein.Representative is the Atkins diet weight loss method proposed by Dr. Robert Atkins (Dr.Robert Atkins).

In the experiment, some of the subjects participating in the experiment can eat fat and protein as they like. There is no restriction on meat, fish and poultry, but sugar should be avoided, and the daily intake should be less than 60 grams (equivalent to 240 calories).Another part of the subjects not only reduced their total calorie intake, but also avoided fat intake.Finally, comparing the dietary results of the two groups of subjects, it was found that the former group compared with the latter group:
1. Weight loss.

2. High-density lipoprotein cholesterol rises.

3. The fat in the blood drops.

4. Blood pressure drops.

5. Total cholesterol remained unchanged.

6. Low-density lipoprotein cholesterol rose slightly.

7. The risk of heart attack is greatly reduced.

Let's look at one of these studies in detail. In 2007, the Journal of the American Medical Association published a weight-loss study by researchers at Stanford University that received $200 million in government funding.It's called the "A TO Z" Weight Loss Study, and it compares four weight loss methods.

1. Atkins weight loss method (A-Atkins): In the first two or three months, only 20 grams of carbohydrates are allowed per day, and then 50 grams, and there is no restriction on the intake of protein and fat.

2. Traditional weight loss (T-Traditional): also known as LEARN weight loss (L-Lifestyle: lifestyle, E-Exercise: exercise, A-Attitudes: attitude, R-Relationships: relationship, N-Nutrition: nutrition) .Limit overall calories, sugar accounts for 55% to 60% of all calories, fat is less than 30%, of which saturated fatty acids are less than 10%, and daily exercise is encouraged.

3. Ornish weight loss method (O-Ornish): Limit the fat in the diet to less than 10%, while promoting moderate diet and exercise.

4. Z-Zone: 30% of the calories in the diet come from protein, 40% from carbohydrates, and 30% from fat.

The following is a comparison of the results of weight changes and heart disease risk factors after one year of subjects who used different weight loss methods.

(End of this chapter)