by Karina Gordin
Vitamin B3, commonly referred to as niacin, is a water-soluble nutrient essential in energy production, metabolism, and DNA repair. As one of eight B-complex vitamins, B3 can be biosynthesized from the amino acid tryptophan but is preferentially obtained directly through food and/or supplements. According to the National Institute of Health, the recommended daily allowance (RDA) for niacin is largely dependent on age, gender, health conditions, and reproductive status, though the average RDA for men and woman is 14 to 16 milligrams a day, respectively. Good sources of niacin include red meat, fish, poultry, legumes (particularly peanuts and green peas), and enriched refined grains.
Top Ten Niacin-Rich Foods:
Turkey—1 breast: 101 mg (over 100 percent DV)
Chicken Breast—3 oz.: 8.9 mg (44 percent DV)
Peanuts—1 cup: 21.9 mg (over 100 percent DV)
Mushrooms—1 cup: 7.6 mg (34 percent DV)
Liver—1 slice: 11.9 mg (60 percent DV)
Tuna—3 oz.: 11.3 mg (56 percent DV)
Green Peas—1 cup: 3 mg (15 percent DV)
Grass-fed Beef—3 oz.: 7.6 mg (36 percent DV)
Sunflower Seeds—1 cup: 3.8 mg (19 percent DV)
Avocado—1 whole fruit: 3.5 mg (17 percent DV)
Though a deficiency in dietary niacin is exceedingly rare in developed countries, factors such as smoking, alcoholism, defective tryptophan absorption, long-term use of chemotherapeutic treatments, and a diet high in processed foods, may contribute to low levels of niacin. Symptoms of mild deficiency may manifest as fatigue, canker sores, depression, vomiting, poor circulation and indigestion; a marked cellular deficiency of niacin—pellagra—is characterized by four “D’s”: diarrhea, dermatitis, dementia, and death. Niacin supplements such as nicotinic acid and nicotinamide are approved by the FDA to treat and prevent deficiency, while pharmacologic doses of over-the-counter prescription niacin may be used with success to address a wide range of commonly occurring conditions.
Top Health Benefits of Vitamin B3
Vitamin B3 has been studied extensively for its role in cardiovascular, digestive, and mental health, as well as supporting the function of more than 200 enzymes in the body. While eating niacin-rich foods is critical for overall health, dermatological therapeutic benefits of topical vitamin B3 are being increasingly studied, particularly in the applications of skin cancer, photosensitivity, and aging.
Skin Health
Three primary forms of vitamin B3 are utilized in topical skincare products: niacinamide, nicotinic acid, and nicotinate esters. The majority of published in vitro and clinical studies demonstrating skin effects have been performed with topical niacinamide—the physiologically active form of niacin. Specifically, niacinamide is a precursor to nicotinamide adenine dinucleotide NAD(H) and nicotinamide adenine dinucleotide phosphate NADP(H)—co-factors involved in a range of metabolic pathways that support optimal skin function.
According to a recent study published in the Journal of Cosmetic Dermatology, topical application of niacinamide has a stabilizing effect on the epidermal barrier, presented as a reduction in trans-epidermal water loss and an improvement in the moisture content of the stratum corneum (outermost layer of the epidermis). Niacinamide administration may lead to an increase in protein synthesis, stimulate ceramide production, accelerate differentiation of keratinocytes, and raise intracellular NADP levels. Additionally, niacinamide may exhibit anti?inflammatory effects in acne, rosacea, and nitrogen mustard?induced irritation (chemotherapy agent). Study authors concluded, “Because of its verifiable beneficial effects, niacinamide would be a suitable component in cosmetic products for use in disorders of epidermal barrier function, for ageing skin, for improving pigmentary disorders and for use on skin prone to acne.”
Niacinamide shows equally promising skin-protective effects inhibiting photo-carcinogenesis in Vivo and in Vitro. Australian researchers recently released a study abstract indicating that the active form of vitamin B3 significantly reduces the incidence of nonmelanoma skin cancers in a cohort previously diagnosed with basal cell carcinoma or squamous cell carcinoma. The researchers conducted a year-long study of 386 people, with an average age of sixty-six years. Half of the study subjects received five hundred milligrams of nicotinamide twice daily, while the remaining subjects were put on a placebo. Researchers found that twice daily administration of vitamin B3 lowered the incidence of developing new skin cancers by 23 percent.
Cardiovascular Health & Cholesterol
Niacin is commonly administered as a pharmacologic agent to regulate abnormalities in plasma lipid and lipoprotein metabolism, and in the treatment of atherosclerotic cardiovascular disease. Supplementing with high-dose niacin has likewise been shown to be beneficial for patients at an increased risk for heart attack, stroke, or other forms of heart disease associated with high low-density lipoprotein (LDL) cholesterol levels, low levels of high-density lipoproteins (HDL), and elevated triglycerides. According to Stephen Sinatra, MD, a board-certified cardiologist and founder of Heart MD Institute, “When it comes to [Lipoprotein(a)], which is by far the most dangerous form of cholesterol, niacin is probably the only nutrient that lowers it. Fish oil, nattokinase, and lumbrokinase can help neutralize the pro-clotting influence of Lp(a), but they don’t reduce it. At the same time, by increasing your HDL cholesterol levels niacin helps to lead to plaque regression. In fact, the higher your HDL levels, the greater the protection in your blood vessels.”
Though vitamin B3 niacin is one of the most reliable and widely used modalities for the treatment and prevention of cardiovascular disease, Sinatra nevertheless cautions regarding skin flushing—a common minor side effect selectively mediated by the release of vasodilatory prostaglandins from the skin. “The only downside to taking niacin is that some people experience a ‘niacin flush.’ This tingly pins-and-needles sensation and sometimes hot flushing of the skin…can occur initially at doses as low as 50 mg a day and typically lasts no more than a half-hour to an hour, then disappears.”
Brain Function
Studies to date find that niacin supplementation may help protect against Alzheimer’s Disease (AD) and other age-related neurodegenerative disorders that result in cognitive decline. A large prospective study, published in the Journal of Neurology, Neurosurgery, and Psychiatry, observed a protective effect of niacin against the development of AD within standard levels of dietary intake—a medical breakthrough that may have substantial public health implications for disease prevention.
Karina Gordin is a Well Being Journal contributing editor.
Further related reading in Well Being Journal feature articles: vitamins and supplements.
Bibliography
K. Karthikeyan, D. M. Thappa, “Pellagra and skin,” International Journal of Dermatology 41, no. 8 (2002):476-481.
J. D. Morrow, J. A. Awad, and J. A. Oates, et al., “Identification of skin as a major site on prostaglandin D2 release following oral administration of niacin in humans,” Journal of Investigative Dermatology 98, no. 5 (1992): 812-815.
A. C. Chen, A. J. Martin, and B. Choy, et al., “A phase 3 randomized trial of nicotinamide for skin-cancer chemoprevention,” New England Journal of Medicine 373, no. 17 (2015): 1618-1626.
D. L. Bissett, K. Miyamoto, and P. Sun, et al., “Topical niacinamide reduces yellowing, wrinkling, red blotchiness, and hyperpigmented spots in aging facial skin1,” International Journal of Cosmetic Science 26, no. 5 (2004): 231-8.
W. Gehring, “Nicotinic acid/niacinamide and the skin,” Journal of Cosmetic Dermatology 3, no. 2 (2004): 88-93.
D.M. Capuzzi, J.M. Morgan, and O.A. Brusco Jr, et al., “Niacin dosing: Relationship to benefits and adverse effects,” Current Atherosclerosis Reports 2, no. 1 (2000): 64-71.
J. Wink, G. Giacoppe, and J. King, “Effect of very-low-dose niacin on high-density lipoprotein in patients undergoing long-term statin therapy,” American Heart Journal 143, no. 3 (2002): 514-8.
J.M. Backes, R.J. Padley, and P.M. Moriarty, “Important considerations for treatment with dietary supplement versus prescription niacin products,” Postgraduate Medical Journal 123, no. 2 (2011): 70-83.
C. D. Meyers, V.S. Kamanna, and M. L. Kashyap, “Niacin therapy in atherosclerosis,” Current Opinion in Lipidology 15, no. 6 (2004): 659-65.
M. C. Morris, D. A. Evans, and J. L. Bienias, et al., “Dietary niacin and the risk of incident Alzheimer’s disease and of cognitive decline,” Journal of Neurology, Neurosurgery, and Psychiatry 75, no. 8 (2004): 1093-9.
“Niacin.” U.S. National Library of Medicine. https://livertox.nlm.nih.gov/Niacin.htm (accessed April 4, 2018).