Can Boosting Metabolism Affect More Than Just Your Waistline?

Metabolism is often thought of as the way our bodies process the foods we eat. We’ve all heard that a “slow” metabolism may lead to weight gain and that those people who never seem to struggle with weight may have “fast” metabolisms. But what does the word metabolism even mean and what does it affect outside of our waistlines?

Technically speaking, the word metabolism refers to all the chemical reactions that occur throughout the entire body. It is true that many of the body’s chemical reactions control the digestion of food, but chemical reactions control so much more than that. In addition to breaking down the food we eat, chemical reactions are responsible for creating the building blocks for essential components of the body, including proteins, DNA, cell membranes, hormones, and steroids. Chemical reactions also process and dispose of waste products, including those that are eliminated from the body in urine.

With these diverse and numerous cellular reactions encompassed by the term metabolism, it’s easy to think these reactions have nothing in common. But these reactions share many common features, including a molecule called nicotinamide adenine dinucleotide (NAD). NAD is a co-enzyme found in all cells that facilitates chemical reactions found across practically every kind of metabolic process.

NAD levels in the body decline with age and patients with certain premature aging syndromes have lowered NAD levels [1-5]. Obesity and metabolic syndrome also alter NAD levels [6]. Many environmental factors whose effects may accumulate with increased age are also known to reduce NAD levels. For example, exposure to UV light reduces NAD levels through chemical reactions that correct DNA damage [7]. NAD levels also rise and fall in a 24-hour cycle as one of our many circadian rhythms [8-9]. Activities that throw off our circadian rhythms, like working at night or travel between time zones, may therefore also impact NAD levels.

All of the factors that can impact NAD levels can also affect the function of the many chemical reactions throughout our bodies that depend on NAD. These factors, among others, contribute to the advice to eat in moderation, to exercise, to get good quality sleep, and to stay active. While aging and many forms of stress are inevitable, making healthy lifestyle choices is a step we can all take to help counteract NAD decline. A healthy cellular metabolism helps us maintain our youthful resilience, which may be even more exciting than just being a tool to manage our waistline.

References

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