Sugar Is Crucial for Immunity: 2 Kinds Boost Immunity and Help You Live Longer

B-cell white blood cell, type of lymphocyte produce antibody molecules. B cell is humoral immunity component of the immune system producing antibodies, protect against pathogens: bacteria, viruses. By Corona Borealis Studio/Shutterstock

Nowadays, the concept of a low sugar and no-sugar diet is very popular. Many people are beginning to pay attention to reducing sugar intake in their diet, and are even implementing a “zero sugar” diet to some extent.

However, a recent study published in the Proceedings of the National Academy of Sciences found that sugar is important for the body’s immune function, and sugar plays a decisive role in the activation of immune cells. When the body has the right amount of sugar, immunity can be activated.

Immune Cells Need Sugar to Obtain the Strength to Fight

Many of our immune cells live in the lymph nodes, and the energy in the lymph nodes is sufficient for their function. “It’s as if the lymph nodes are filled with lunch boxes. These cells can be permanently filled with energy, and even grab a box to go when they leave the lymph nodes to circulate through the body,” said the head of the study, Associate Professor Marc Veldhoen of the Instituto de Medicina Molecular João Lobo Antunes (IMM).

When immune cells leave the lymph nodes and kill viruses, they can even bring some “lunch boxes” with them to provide themselves with energy. It’s like a person who has eaten his fill at home and brings some more to work.

However, there are some immune cells that don’t live in the lymph nodes, but in tissues, such as the gut. They don’t have access to the same level of energy resources. These immune cells stay in a constant state of partial activation and are prepared to react to issues like infections, according to Veldhoen.

They need to “eat” glucose to replenish energy and become active. Using the gut of a mouse as a model, the researchers found that the activation of resident lymphocytes in the gut and the time it took for infections to clear depended on how much sugar was available.

“We found that in mice infected with an intestinal pathogen, the local availability of glucose can determine the activation of the resident lymphocytes and to a faster clearance of infection,” explained another researcher, Spela Konjar.

People Are Healthiest When Carbohydrates Account for 50 to 55 Percent of Total Energy

The human body obtains energy from three macronutrients: carbohydrates, protein, and lipids.

Carbohydrates are also known as saccharides. The main carbohydrates that are eventually converted into glucose are starch and sucrose, which are part of the larger carbohydrate family.

Since our body needs carbohydrates to get glucose, how much should we consume to be healthy?

A study published in The Lancet followed more than 15,000 American adults aged 45 to 64 over an average of 25 years.

They found that, out of the total energy obtained from carbohydrates, protein, and fat, people lived the longest when 50 to 55 percent of energy was derived from carbohydrates.

When the energy intake through carbohydrates is less than 50 percent or more than 55 percent of the total energy, it affected people’s lifespan. In other words, eating too much or too few carbohydrates could have a negative health impact.

The researchers estimated that a 50-year-old with intake of less than 30 percent of energy from carbohydrates would have a projected life expectancy of 29.1 years; a 50-year-old with 65 percent or more of energy from carbohydrates would have a projected life expectancy of 32 years, and someone who consumed 50 to 55 percent of total energy from carbohydrates would have a projected life expectancy of 33.1 years.

Supplement ‘Good Carbs’ to Supply the Right Kind of Sugar

So, how do we choose good carbohydrates—a source of high-quality glucose—for our body?

1. Eat natural starchy foods

The main source of glucose in our diet is starch.

Starch is a nutrient produced by photosynthesis in plants and is our body’s preferred fuel. Each plant produces its own unique starch, but all starch breaks down into glucose when digested. Each gram of starch or sugar will furnish 4 calories of energy.

Please remember that not all carbohydrates are the same.

There are many different types of carbohydrate-containing foods, and they all have different health effects. Sources of starch can be divided into two categories. One is the starch in natural foods, such as potatoes, sweet potatoes, pumpkins, and other root vegetables, as well as brown rice, corn, and other natural grains.

The other type is refined starch. Refined starch is made from natural foods that have been further processed to remove most of the fiber and many nutrients, such as white rice and white flour. Since there is no fiber and other substances, refined starch will break down quickly, causing a rapid rise in blood sugar level.

It is best to choose starch from natural foods. Since these starches have a lot of fiber and other substances wrapped around them, they are not easily digested. The presence of organic acids slows down the emptying of the stomach, making the release of sugar relatively slow. This means that while the body’s getting sugar energy, the impact on blood sugar is relatively small.

2. Eat natural sugars

Another source of glucose is sucrose. When sucrose is digested, it produces 50 percent glucose and 50 percent fructose.

Natural sucrose is found in many fruits, vegetables, and grains.

Many fruits contain sucrose, glucose, and fructose. For example, the ratio of glucose, sucrose, and fructose is about 2:1:2 in bananas, which are  commonly eaten. Peaches, oranges, apples, peas, and mangoes all contain large amounts of natural sucrose, and tomatoes and blueberries have half of their sugars as glucose.

Fruit juice is not the same, as it has the fiber and some of the ingredients in the fruits removed, making the fruits’ nutrition no longer complete. People can also easily exceed their daily fruit or sugar intake when drinking juice instead of eating fruit.

When eating whole fruits, with the chewing action and a lot of fiber intake, people usually won’t eat too much, unlike simply drinking fruit juice. And the whole fruit contains a good mix of natural nutrients, including fiber, micronutrients, and other substances that work together to slow down the absorption of sugar in the body.

There is another type of sucrose extracted from food, which is the refined sugar we often eat, such as white sugar. Sucrose is added to most processed foods. Sugar is also added to products that do not taste sweet, such as seasonings and sauces.

In fact, we do not need to get any sugar from added sugars. Added sugars only provide calories but not nutrients, which in the long run can damage one’s metabolism.

Artificially refined foods, such as cane sugar or starch, can provide a sweet, silky texture, but oftentimes, some of their good ingredients are removed. They can only provide people with the short-term pleasure of “eating sugar,” but cannot provide other nutrients, and in the long run will lead to addiction and other hazards. To really quit sugar, you must first quit this type of sugar.

There is a simple and easy way to do this—choose natural foods as much as possible to get sugar and energy from them.