Metabolism is a crucial process in our bodies that converts food into energy to fuel various bodily functions. However, the metabolic process produces reactive oxygen species (ROS) that can cause damage to cells and tissues if not neutralized. The body has mechanisms to handle ROS, but excessive ROS production can cause oxidative stress and harm the body. One way to deal with oxidative stress is by taking antioxidants, which neutralize ROS. This article explores the role of metabolism, ROS, and antioxidants in health and disease.
Metabolism is the set of chemical processes that occur in our cells to convert food into energy. The metabolic process involves two stages: catabolism, which breaks down food molecules to release energy, and anabolism, which uses the energy to build molecules like proteins and fats. The catabolic process produces ROS, which are highly reactive molecules that can damage cells and tissues. The body has endogenous antioxidants like superoxide dismutase, catalase, and glutathione peroxidase, which neutralize ROS and protect the body from oxidative stress.
Oxidative stress occurs when there is an imbalance between ROS production and antioxidant defense, leading to the accumulation of ROS and damage to cells and tissues. Oxidative stress has been linked to various diseases like cancer, diabetes, heart disease, Alzheimer’s disease, Parkinson’s disease, and aging. The ROS produced during the metabolic process are one of the major sources of oxidative stress in the body. Therefore, maintaining a balance between ROS production and antioxidant defense is crucial for good health.
Antioxidants are molecules that neutralize ROS by donating an electron to stabilize them. Antioxidants can be endogenous, like glutathione and superoxide dismutase, or exogenous, like vitamins C and E, carotenoids, and flavonoids. Antioxidants play a crucial role in maintaining the redox balance in the body and protecting cells and tissues from oxidative stress. However, taking antioxidants in high doses may not always be beneficial, as excess antioxidants can interfere with normal cellular processes and even promote oxidative stress.
The concept of the uncoupling of oxidative phosphorylation is related to ROS production during metabolism. Uncoupling refers to the process by which the electron transport chain in the mitochondria becomes uncoupled from ATP synthesis, leading to a high rate of electron flow and ROS production. Uncoupling agents like 2,4-dinitrophenol (DNP) and carbonyl cyanide-4-(trifluoromethoxy)phenylhydrazone (FCCP) can increase ROS production by uncoupling the electron transport chain. However, the body has mechanisms to deal with ROS produced during uncoupling. For instance, the uncoupling protein 1 (UCP1) in brown adipose tissue can dissipate the proton gradient and reduce ROS production. Moreover, increasing the body’s metabolic rate through exercise can induce adaptive responses that increase antioxidant defense and reduce oxidative stress.
The rate of metabolism is often used to measure the body’s energy expenditure, with a high metabolic rate indicating a high rate of energy expenditure. However, some people believe that a high metabolic rate can lead to nutrient depletion and oxidative stress. This idea is based on the rate-of-living theory, which suggests that organisms have a limited lifespan because their cells get damaged by ROS produced during metabolism. However, this theory has been challenged by recent evidence suggesting that high metabolic rate does not necessarily lead to oxidative stress and damage. Instead, the body has adaptive responses to increase antioxidant defense and repair mechanisms in response to increased metabolic demands.
The debate on the role of macronutrients like sugar and starch in metabolism and oxidative stress has been ongoing for years. Some people believe that consuming large amounts of sugar can lead to nutrient depletion.
So does sucrose (table sugar) boost metabolism? Maybe so, and it does so without some of the harmful metabolic effects of starch. also stated that fructose and sucrose safety have been assessed to some extent, given that they have been consumed worldwide for over a century, and that it is probably better to have an increase in triglycerides from sucrose than to endure the constant cortisol and insulin due to high starch and glucose intake. Triglycerides correlate negatively with cardiovascular disease mortality and act as inert biochemical agents, and it’s more important to worry about non-esterified free fatty acids (NEFA).