The Good and Bad of Sugars

Known as “the sweetest killer” and “a poison more addictive than drugs”, sugar is consumed by everyone. According to Dr. Heather Moday, an American immunologist, during the Covid-19 pandemic, sugar is the worst food for your immune system.

What Exactly Is Sugar?

Sugar is a food that everyone is very familiar with, and it’s ubiquitous in our lives. We need sugars to maintain our health, and it can also bring relaxation and pleasure to us. However, sugar is like a double-edged sword that can also damage our health if left unchecked. So, what exactly is sugar?

Sugar is an umbrella term for a large group of carbohydrates. Common sugars include:

1. Glucose

Glucose is an energy-supplying substance that the human body can directly utilize, as it is used to supply energy to the brain. Excess glucose is stored in the body in the following forms:

• Converted into liver glycogen and muscle glycogen, and released into the blood when we are hungry to supply energy to the body
• Reserving energy for the liver and muscles
• Converted to fat

Glucose is relatively rare in nature. The most common is in the form of starch in food.

2. Fructose

Fructose is a sugar that is abundantly present in fruits, honey, and sweet vegetables such as beets, potatoes, carrots, and onions. It is the “sweetest” of all sugars. It is 1.7 times sweeter than sucrose.

Fructose cannot be directly used for energy in the body, and excess fructose cannot be converted to glycogen storage like glucose, so it is mainly converted to fat. Fatty livers, obesity, and some other problems are mainly related to fructose. In addition, fructose reduces the body’s sensitivity to insulin and its ability to process fat, thus increasing the risk of diseases, such as heart disease and fatty liver disease.

However, eating fruits in appropriate moderation is beneficial and harmless to the human body, because the sugar in fruit is not like free sugars, such as granulated sugar, but is encapsulated inside the cells, as the cell walls of plants prevent fructose from being absorbed by the body too quickly.

What we need to be more vigilant about is not the natural sugars in fruits and vegetables, but the “free sugars”, that is, “artificial sugars”, such as refined white sugar, rock sugar, granulated sugar, honey, high-fructose corn syrup, and fruit juices. They can make blood sugar levels rise rapidly.

3. Sucrose

Sucrose is derived from sugar canes. Common sugars used in the food industry, such as white sugar, brown sugar, and rock sugar are all basically composed of sucrose.

4. Lactose

Lactose, mainly derived from milk, is beneficial to the health of intestines. However, some people lack lactase in their intestines and cannot digest lactose. For them, after drinking milk, they will develop lactose intolerance, and this may cause diarrhea.

5. Polysaccharides

Polysaccharides are sugar chains composed of many glucose molecules. Starch and cellulose in rice and noodles are examples of polysaccharides. Cellulose comes from grains, fruits, and vegetables, and is very important to human body’s health.

Sugar is necessary to maintain our health, but we will need to rationally face some of the health problems it also brings.

Is Sugar More Addictive Than Drugs?

As aforementioned, although fructose is high in sweetness, moderate intake of fruits and vegetables is beneficial to the human body. What we really need to be wary of is artificially added free sugars, such as sweet chocolates, cakes, and other sweets that many people love.

We all know that children love to eat sugar. This is because children need a lot of energy when they are growing up. In addition, sugar can also activate the “pleasure centers” of our brain and trigger the release of dopamine, which brings a sense of pleasure.

However, this can lead to addiction. There is even a saying that sugar is more addictive than drugs.

In 2007, a study by the University of Bordeaux in France conducted a particular reward experiment with rats. In this experiment, two levers were placed in front of the rats for them to choose freely. Choosing Lever C would give them the “reward” of cocaine (an addictive drug); choosing S would give them some water with saccharin, which has no calories, just a sweet taste.

It is generally assumed that rats would choose cocaine, which is highly addictive. Nevertheless, the results were very surprising. From the second day after the start of the experiment, the rats were more willing to choose Lever S (saccharin). Fifteen days later, 94 percent of the rats were more willing to choose the lever that would get them saccharin.

To find out whether it was the chemicals in saccharin that had an attractive effect, or just the sweet taste, scientists did another study with sucrose and found that rats did have the same preference for saccharin and sucrose.

The researchers therefore concluded that the sweet taste of sugar can be addictive.

Moreover, scientists also found that sugar has almost the same effect on the brain as drugs, and is several times more addictive than cocaine. Eating sugar causes the brain to produce dopamine, which causes pleasure and makes people “sugar addicts.”

The Worst Food for the Immune System

Compared with other addictive substances, “sugar addiction” affects our body in a more subtle way, like a “chronic poison.”

Dr. Heather Moday, an American immunologist, pointed out that during the Covid-19 pandemic, there is one food that is the worst for the immune system, and that is sugar.

The American Journal of Clinical Nutrition conducted a research experiment. After a group of subjects fasted overnight, they took 100 grams of free sugar orally on an empty stomach. As a comparison, another group of subjects took the same amount of starch orally on an empty stomach. The experiment found that the phagocytic ability of phagocytes of the immune system is greatly reduced for people who took free sugar orally. The maximum reduction occurred between one and two hours after ingesting sugar, which was 50 percent lower than that in the fasting state; even after five hours, immunity was still affected.

In contrast, the control group that ingested starch did not show a decline in immunity. Therefore, eating a moderate amount of rice, noodles, and steamed bread will not harm the immune system.

We just saw that after ingesting free sugars, the “combat power” of phagocytes dropped by nearly half. However, the negative impact of excessive intake of sugar on the immune system is not limited to inhibiting the functions of phagocytes.

A high-sugar environment can also cause chronic inflammation and inhibit all aspects of the immune system, including white blood cells, natural killer cells, macrophages and T cells, resulting in a decrease in the comprehensive ability of the human body to recognize and kill germs. Also, another study found that 50 percent of patients hospitalized with Covid-19 in the United States have diabetes or obesity.

Therefore, to improve our bodies’ natural immunity, we must pay more attention to sugar reduction.

Eating Less Sugar is Anti-Aging

Eating too much sugar is known to have several common health effects, such as tooth decay, weight gain, obesity, and diabetes. However, additionally, the increase in blood sugar level caused by consuming sugar will soak the body’s cells in a high-sugar environment, which will produce advanced glycation end products (AGEs).

AGEs are normally produced by the body’s metabolism, and the ability to remove AGEs decreases with age. It has been shown that AGEs contribute to increased oxidative stress and inflammatory responses, accelerate aging and lead to many chronic degenerative diseases, such as:

Diabetes
Atherosclerosis
Osteoporosis
Kidney diseases
Neurodegenerative diseases
Cancer
Skin degeneration

As we all know, dishes such as braised pork and barbecued meats have a special aroma, and baked cakes also have an attractive flavor. This type of flavors come from protein glycosylation (the Maillard reaction). After dry heat cooking (e.g. baking, frying, and roasting), AGEs will increase 10 to 100 times.

How does one avoid the generation of AGEs? Scientific studies have discovered that cooking with moist heat, shorter cooking times, lower temperatures and adding acidic ingredients such as lemon juice or vinegar, can significantly reduce AGEs. So when eating a steak, it makes sense to put a wedge of lemon next to it.

In addition, beef and other red meats contain more AGEs than white meats. Therefore, for our own health, we can try to eat less roasted, fried beef, and eat more beef stew instead, and the amount of AGEs will significantly decrease.

How much sugar should we eat every day?

Although an excessive intake of sugar is unhealthy, it is also essential for maintaining our body functions. So, what amount of sugar should we consume daily?

According to the World Health Organization’s (WHO) latest dietary guidelines released in 2015, the amount of free sugar should be reduced to less than 5 percent of the total daily calorie intake, and no more than 25 grams (six teaspoons), in order to avoid obesity, tooth decay, diabetes, heart disease, vascular diseases and even cancer.

Best Way to cut Sugar

In order to improve health and the immune system, people who are accustomed to eating sweets can consider reducing sugar. To reduce sugar, first of all, we must learn to read nutrition labels on food packaging. (Sugar can go by many names, including: Agave nectar, Brown sugar, Cane crystal, Cane sugar, Corn sweetener, Corn syrup, Crystalline fructose, Dextrose, Evaporated cane juice, Organic evaporated cane juice, Fructose, Fruit juice concentrates, Glucose, High-fructose corn syrup, Honey, Invert sugar, Lactose, Maltose, Malt syrup, Molasses, Raw sugar, Sucrose, Syrup)
Check the sugar content of every item in your pantry. Also, eat less overly processed foods; and eat more carbohydrates in the form of “plain-tasting” vegetables, beans, fruits, nuts or seeds.

However, we should not completely eliminate all sugars, but to have the right intake.

In fact, we often eat sugar, not “rationally” for the needs of the body, but to satisfy an emotional desire. Queensland University of Technology (QUT) researchers have found that excessive sugar intake increases dopamine levels in a similar way to drugs, such as cocaine. So quitting sugar addiction is similar to quitting drug addiction. If you refrain from consuming too much sugar, the desire to eat sugar will weaken; but if you indulge one more time, then the desire will increase, and the next time will be even more difficult.

In addition, scientists have also conducted another experiment, in which one group of rats were fed to be 100 percent full, whereas another group were 70 percent full. Guess which group of rats lived longer? It turns out that the rats that were 70 percent full lived 20 percent longer than the first group.

If something tastes well, we don’t have to eat a lot of it. Instead, we can savor and enjoy its taste. Modern people pay attention to a certain quality of life. To be a person good taste, we might as well start with eating: savor the tastes and properly control excessive desires, which will also bring many benefits to our health.