Vitamin B-3, or niacin, is a nutrient you can get from your diet by eating bread, fortified cereals, legumes, seeds, salmon, meat or poultry. Adding a niacin supplement to your diet may further boost your heart health, energy levels and neurological functions. But be careful not to take too much. Although your body doesn’t store this water-soluble vitamin, niacin can be dangerous in high doses.
Niacin protects your heart by regulating blood cholesterol levels. The vitamin helps convert small, low-density lipoprotein molecules into larger particles that are easier for your body to process. It goes a step further and helps lower your triglycerides, too. Niacin also has been shown to elevate high-density lipoprotein -- the “good” cholesterol in your body. Ultimately, improved cholesterol ratios lower your risk of contracting heart disease. However, your doctor will have to prescribe an individualized dose of niacin if your cholesterol levels are abnormal. Over-the-counter dosages may not be sufficient.
Your body uses glucose from carbohydrates as its main source of energy. Fat and protein are also sometimes used for fuel, or at least stored for backup energy if glucose isn’t available. With the help of the rest of the B vitamins, niacin works to convert these macronutrients into usable fuel supplies. Your system starts running low on this fuel if you don’t have enough niacin and B vitamins to aid in all the conversion steps. This is why you might feel fatigued if your niacin intake isn’t adequate.
Niacin is one of several nutrients that help your nervous system function. Your nervous system’s jobs include sending signals to and from your brain, regulating voluntary and involuntary movements, and keeping organs running. Thus when you don’t regularly consume niacin, these functions might not operate as they’re supposed to. You can have headaches, experience memory loss, feel depressed and become disoriented.
Amount to Take
Your niacin supplement should give you just the recommended dietary allowance, unless your doctor says otherwise. Men need 16 milligrams, while women require 14 milligrams each day, according to the Food and Nutrition Board of the Institute of Medicine. Women who are pregnant or breast-feeding need to increase their intake to 18 milligrams and 17 milligrams, respectively. Taking more than 35 milligrams daily, which is the tolerable upper level, could lead to severe skin flushing, vomiting and itchiness all over your body. Over time, high doses can damage your liver.