This article was originally published as a guest editor post at foodpharmacy.se
By: Graeme Jones, clinical physiologist and CEO at Nordic Clinic Stockholm.
Since my last article and travels over the summer in Sweden I sadly have to report that I have not yet found the fountain of youth. As we have discussed so far in these series of articles all about aging, our chronological age (i.e. the number of years we have lived) can be very different to our biological age (the age of our cells). Our goal at Nordic Clinic is to slow that rate of aging. Why? Simply put, the faster we age, the greater the risk of chronic disease, and that is what really kills us in the West. However, calorie and protein restriction, regular exercise and not eating a western diet have come to our rescue, giving us ways to slow the aging process. Until we can take a drink from the fountain of youth, what else can we do?
As far as cellular pathways of aging go, something called nicotinamide adenine dinucleotide (let’s use its abbreviation NAD+ from here) has no rival. Many clinical trials are either completed or underway looking at the effects of NAD+ on aging. It all started with the observation that NAD+ levels decrease with age.
In biology, enzymes get things done. Basically, every biochemical process uses one or more enzymes to accomplish its task. But many enzymes cannot act alone, they require cofactors to assist them in their processes. In many instances, vitamins act as precursors to cofactors.
NAD+ is a form of vitamin B3 (niacin) that acts as a cofactor for several important pathways in aging. On the one hand, NAD+ is essential for energy metabolism. On the other, NAD+ also plays a role in DNA repair and inflammation. It’s these divergent roles of NAD+ that make it so important for healthy aging.
NAD+ For Fighting Inflammation, Getting Good Sleep and Repairing our DNA
We create energy from our food to fuel cellular processes. NAD+ plays a big role in this process – low NAD+ means less energy creation. Other enzymes require NAD+ as well. Sirtuins are NAD+ dependent enzymes that play a role in repairing our DNA and regulating circadian rhythms (our evolutionary preferred wake/sleep patterns), helping us to get restorative sleep. Certain immune cells called CD38 that play a role in inflammation and appear to be largely responsible for the age-related decline of NAD+, also require NAD+ (1).
Foods To Boost NAD+
NAD+ seems important so far, no doubt. Here we have an enzymatic cofactor that declines with age and plays a role in multiple pathways that keep us healthy. How do we get more of it? One important factor for maintaining adequate NAD+ levels is getting enough vitamin B3 in our diet. B3 comes from avocado, anchovies, salmon, mushrooms, green peas and tuna. However, some of the highest levels come from meats, such as liver, turkey, chicken and beef, if you are a meat eater.
Another potential avenue for increasing NAD+ levels in the body is inhibition of CD38. Since CD38 drives the age-related decline in NAD+ and is induced by inflammation, molecules that inhibit CD38 or reduce inflammation may be useful to slow down NAD+ decline. Potential inhibitors of CD38 include the polyphenols (micronutrients packed with antioxidants that we get through certain plant-based foods) apigenin, which you can get from parsley, chamomile, celery, vine-spinach, artichokes, and oregano. Another one is quercetin, which you can get from apples, honey, raspberries, onions, red grapes, cherries, citrus fruits, and green leafy vegetables. (2)
Maintain NAD+ Through Optimal Nutrition and Lifestyle
Humans need adequate NAD+ to maintain health throughout their lifespan. Unfortunately, as we grow older, NAD+ levels decline. This leads to a decrease in our ability to generate energy, repair DNA damage, and build strong circadian rhythms. Over time, we accumulate damage and disease risk increases.
Currently, the best practices to maintain NAD+ levels as we age include exercise, calorie restriction, limiting alcohol intake, eating foods high in Niacin and polyphenols, and building strong circadian rhythms. Each one of these factors boosts NAD+ (3). Hopefully future research will uncover additional ways to help prevent the age-related decline in NAD+.