A metabolic process that occurs in the liver when fasting results in ketone bodies. These ketone bodies are molecules that are water-soluble and provide nutrients to cells when glucose is not readily available. The molecules contain ketone groups generated from fatty acids in the liver, by which they obtain their name. This metabolic by-product has been demonstrated to boost immunity and fight off invading pathogens and disease.
A recent study on Immunity by Dr. Russell Jones and colleagues at the Van Andel Institute suggested personalized diet recommendations to mediate cancer, infection, and other diseases. The study conducted helps scientists and doctors better understand how diet can affect the immune system. Jones and colleagues found that ketone bodies, when rapidly produced, during a shortage of glucose or sugar, become the main source of nutrients for cells. This commonly occurs during fasting, when the cells are deprived of nutrients or exercise when the body's cell are rapidly burning through nutrients. As a result, the liver produces ketone bodies to maintain healthy function in the brain and other organs. The study accidentally found and demonstrated that these ketone bodies support and strengthen immune cells.
T cells are a type of immune cell responsible for killing invading pathogens. They are critical to the immune system, and we rely heavily on them to protect us against disease. T cells utilize glucose to function properly and stay alive. Interestingly, Jones and colleagues found that T cells prefer ketone bodies over glucose. When T cells absorbed ketone bodies instead of glucose, they had improved function and reprogrammed the cells to better neutralize pathogens. Alternatively, when the ability to process ketone bodies was lost, the T cells became defective and lowered their ability to kill pathogens.
Jones and colleagues suggest that ketone bodies may be an evolutionary trait that improves the immune system when nutrients are limited. This is similar to when a person is sick, and ketone bodies are present or increased due to loss of appetite to improve immunity. The work suggests how different nutrients duel specific cellular functions and piques interest in nutrient diversity for different cell types in the immune system.
Jones and colleagues, for the first time, found that ketone bodies improve immune cell function, specifically T cells. Although T cells are one of the main cell types affected by this nutrient source, it demonstrates how different nutrients can be optimal for different cell types and help an individual build a stronger immune system. The study suggests that fasting or intermittent fasting is healthy for people due to ketone body production for immune cells; other studies indicate that fasting may hamper immunity. With contradicting literature, it is imperative that more work is done to reach a final conclusion. This study highlights the critical understanding of diet and immunity. Overall, it remains inconclusive whether fasting is better or not for you, but much of the literature agrees that too much of anything is bad for you. Therefore, it might be a matter of balance that helps to drive improved immunity and better quality of life.