Basic Description Role in Health Support Summary of Food Sources Nutrient Rating Chart Impact of Cooking, Storage and Processing Risk of Dietary Deficiency Other Circumstances that Might Contribute to Deficiency

Relationship with Other Nutrients Risk of Dietary Toxicity Disease Checklist Public Health Recommendations References

Basic Description

Niacin is a blanket term for a family of compounds with vitamin B3 activity. The terms "niacin" and "vitamin B3" can be used interchangeably, and whenever you find either term on our website, we are referring to the same group of compounds. Basic types of vitamin B3 include nicotinamide, nicotinic acid, and several active enzymatic forms, each of which can be obtained from food. In research studies, nicotinamide is used as a standard of measurement for calculating the vitamin B3-activity associated with each forms of niacin, prompting researchers to use the term "NE" when referring to B3 measurements. "NE" in this situation stands for "niacin equivalents." Many public health organizations make B3 recommendations in terms of "milligrams of NEs" per day. When you see this type of reference, it simply means that all forms of B3 found in whole foods count as good ways to meet your daily B3 needs.

You may have heard the term "pellagra," and if you associate this term with diet- and nutrition-related problems, you are correct. Pellagra is the name of a disease that is characterized by nutrient defiency, and primarily deficiency of vitamin B3. It took a long time for healthcare community—both in the U.S. and worldwide—to recognize that dietary changes as simple as adding animal foods and legumes to a meal plan could help prevent pellagra. Between 1900 and 1940, more than 100,000 people in the United States—mostly those who were poor, African-American, female, and from southern states—died from an epidemic of pellagra stemming from poverty and malnourishment. This epidemic was wrongly ascribed to several possible causes, including infection. It was also a primary reason for steps taken by the U.S. Department of Agriculture (USDA) in 1938 to authorize the enrichment of wheat flour with niacin. ("Enrichment" refers to the addition of nutrient supplements during food processing.)

Consumption of enriched wheat flour, however, is by no means required for adequate niacin intake. Your diet is likely to have the recommended daily amount of B3 if you have multiple daily servings of whole, natural foods across a wide variety of food groups.

The World's Healthiest Foods list contains four excellent sources of niacin—tuna, chicken, turkey, and crimini mushrooms. We also list six very good sources and 34 good sources. A number of our recipes are very niacin rich, including 13 that contain more than the Dietary Reference Intake (DRI) requirement.

Role in Health Support

Energy Production

Like the other B complex vitamins, niacin is important in energy production. Two unique forms of vitamin B3 (called nicotinamide adenine dinucleotide, or NAD, and nicotinamide adenine dinucleotide phosphate, or NADP) are essential for conversion of dietary proteins, fats, and carbohydrates into usable energy. Niacin is also used to synthesize starch that can be stored in muscles and liver for eventual use as an energy source.

Antioxidant Protection

The same niacin-containing enzymes that are involved in energy metabolism, NAD and NADP, work by quenching free radicals. This process is not only important in energy production, but in protecting your body against excessive tissue damage. While most lay person nutrition sources omit niacin from the list of dietary antioxidants, researchers are aware of this connection, and have studied it extensively, particularly in people with diabetes.

Summary of Food Sources

Other than crimini mushrooms and asparagus, all of the excellent and some of the very good sources of B3 in our rating system are animal-derived foods. Six of these contain 50% or more of the DRI recommendation for the nutrient.

The good sources of niacin come from many different food groups. We see legumes (particularly peanuts and green peas) represented. A number of vegetables, particularly root vegetables and leafy greens, also show up as good niacin sources. We also find fruits (cantaloupe), nuts/seeds (sunflower seeds), and grains (brown rice, barley).

It is pretty easy to build a menu with a full day's supply of B3 using a small number of the World's Healthiest Foods. For example, you could include a recipe that includes both Green Peas and Crimini Mushrooms at lunch. At dinner, you could enjoy a recipe that features fish such as our 15-Minute Salmon with Mustard Dill Sauce. And with those two dishes, you've well exceeded the DRI for niacin.

Or if you'd like a more direct way to exceed your daily B3 requirement, try our Warm Spinach Salad with Tuna recipe and get more than twice the DRI from this single meal.

Nutrient Rating Chart

Introduction to Nutrient Rating System Chart

In order to better help you identify foods that feature a high concentration of nutrients for the calories they contain, we created a Food Rating System. This system allows us to highlight the foods that are especially rich in particular nutrients. The following chart shows the World's Healthiest Foods that are either an excellent, very good, or good source of vitamin B3. Next to each food name, you'll find the serving size we used to calculate the food's nutrient composition, the calories contained in the serving, the amount of vitamin B3 contained in one serving size of the food, the percent Daily Value (DV%) that this amount represents, the nutrient density that we calculated for this food and nutrient, and the rating we established in our rating system. For most of our nutrient ratings, we adopted the government standards for food labeling that are found in the U.S. Food and Drug Administration's "Reference Values for Nutrition Labeling." Read more background information and details of our rating system.

Impact of Cooking, Storage and Processing

In terms of storage, the B3 in whole natural foods tends to be relatively stable. If you store foods using the approaches we recommend in our website food profiles (in the sections entitled, "How to Select and Store," the B3 in your foods should still be there when you are ready to consume them.

However, cooking is another matter. As a water-soluble vitamin, B3 is susceptible to leeching out of your food and into cooking water. We've seen a study of the boiling of meat where about twice as much B3 was lost from boiling versus pan-frying. While we are not recommending that you pan-fry meats, we view this research as consistent with the principle that a water-soluble vitamin like B3 can leech into cooking water. Our Healthy Steaming method allows you to avoid submersion of foods in water; our Healthy Sauté methods allows you to use a relatively small amount of liquid, and our Quick Boil method helps you keep the time of submersion in water to a minimum. All of these methods are intended to help you reduce nutrient loss during cooking, especially loss of water-soluble nutrients like B3.

You might be interested to know that in many foods traditions—including Native American traditions—communities eating local, seasonal, whole, natural foods developed ways of improving their B3 intake. One way involved the preparation of corn. In many tribal traditions across North America where corn (traditionally called maize) played an important role in the daily meal plan, hominy (made from corn kernels) and other corn dishes were prepared by soaking and/or cooking corn mixtures with a compound made from wood ash. In this process, ash from wood fires was boiled down to produce a white residue called "potash"—literally "pot ash." From a chemical standpoint, potash provided a variety of potassium-containing salts and especially potassium carbonate. Like lye (sodium hydroxide) and lime (calcium hydroxide), the boiling of corn mixtures in potash was able to create a very alkaline fluid that helped change the chemical structure of the corn. (Even today, you will find lime—calcium hydroxide—to be a very common ingredient in many store-bought tortillas, tamales, and tortilla chips. Within the context of today's food industry, the processing of corn in a "limewater" solution allows formation of a dough from the corn.) Within traditional Native American cuisines, however, one of the most important changes brought about by the potash soaking and boiling of corn was to make its B3 much more available for digestion when the corn was eaten. This cooking method helped many groups of Native Americans who were dependent on corn for their nourishment to greatly lower their risk of B3 deficiency and pellagra.

Risk of Dietary Deficiency

Many circumstances have combined to dramatically reduce the risk of B3 deficiency in the average U.S. diet. These circumstances include widespread consumption of animal foods—including chicken and turkey—as well as addition of B3 to grain products (like wheat flour or corn meal). The average U.S. adult (age 20 and over) consumes about 26 milligrams of B3 per day, or about 160% of our WHFoods recommended intake amount of 16 milligrams.

Even though animal foods and fish are our richest sources of B3 (with single servings often providing 25% or more of the needed daily amount), it is not difficult for a vegetarian diet to provide ample amounts of B3. Mushrooms, legumes, seeds, and fresh vegetables are often rich in B3. As an example, one serving of crimini mushrooms, one serving of peanuts, one serving sunflower seeds, one serving of sweet potato, and one serving of brown rice add up to about 825 calories and 100% of your daily B3 requirement.

Other Circumstances that Might Contribute to Deficiency

In industrialized countries, world, most instances of vitamin B3 deficiency appear to be related to medical conditions. By far the most likely reason to see niacin deficiency is alcoholism, a condition that can compromise not only B3 status, but the status of many other nutrients as well. .

Relationship with Other Nutrients

The traditional definition of a vitamin is a compound necessary for normal growth and nutrition that is needed from food since the human body cannot produce it. While we don't find any basic fault with this definition, we also know that in a technical sense, it is not always correct. In the case of some vitamins, there are ways for the body to make the vitamin even if the vitamin is not preformed and already existing in food. Interestingly, niacin is one of the vitamins that "breaks the rules" in terms of the traditional definition.

Niacin can be synthesized in the body from the amino acid tryptophan. So in principle, it might be possible for a person to get all of the niacin they need from the tryptophan found in protein-rich foods, even if those foods contained no niacin. From a practical standpoint, however, many protein-rich foods (like animal foods) are also rich in niacin, so that there would be no practical need to take the tryptophan in these foods and convert it into niacin. (The rate of conversion from tryptophan to niacin in the human body is estimated to be somewhere in the range of 60:1, meaning that 60 milligrams of tryptophan would be required to create one milligram of niacin.) There is no question that the human body—under some circumstances, which are still being actively investigated—takes tryptophan and converts it into niacin. But exactly how important this process is to our B3 status is not clear. Among the complicated issues in this area of tryptophan-to-niacin conversion is the role of other nutrients required for conversion. Vitamin B6, for example, is clearly needed for conversion of tryptophan into niacin, and researchers aren't clear how relative deficiencies in B6 might affect the conversion process. We look forward to future research in this area that will help us better understand this aspect of B3.

Risk of Dietary Toxicity

There is no known risk of dietary toxicity from naturally occurring niacin in foods. Even in the case of our most niacin-rich animal meats and fish, we are not aware of any research showing toxicity risk for B3. In keeping with this clean research bill of health, the National Academy of Sciences (NAS) has not set any Tolerable Upper Intake Level (UL) for B3 when obtained from whole, natural foods. However, the NAS has set ULs for B3 in supplement form and in processed foods that have been fortified with B3. While we do not believe that fortification with B3 generally serve to increase risk of excess B3 intake, we would point out that some ready-to-eat (RTE), heavily fortified breakfast cereals can sometimes contain relatively high amounts of B3 (in some cases, up to 20 milligrams per 1-cup serving, although 5-10 milligrams is a more common range in fortified RTE cereals). In the case of a young child under the age of 8 years, this amount of B3 from a fortified food could actually exceed the UL as established by the NAS. We would like to be very clear that we have seen no evidence to show that intake of B3 from fortified foods has resulted in any actual health problems. However, simply looking from the perspective of the ULs and B3 content from specific fortified products, we can see how the ULs could potentially be exceeded under certain circumstances, especially for younger age groups. Below is a complete list of ULs for vitamin B3 intake from supplements and fortified foods:

Upper Limits for Vitamin B3 From Supplements and Fortified Foods

• 1-3 years: 10 milligrams
• 4-8 years: 15 milligrams
• 9-13 years: 20 milligrams
• 14-18 years: 30 milligrams
• 19 years and olders: 35 milligrams
• Pregnant or lactating women, 18 years and younger: 30 milligrams
• Pregnant or lactating women, 19 years and older: 35 milligrams

Just to repeat: the above limits do not apply to vitamin B3 when it is consumed from whole, natural foods. When consuming vitamin B3 from whole, natural foods, this general adult limit of 35 milligrams can be exceeded and is not considered to be a toxicity health risk.

Disease Checklist

• Pellagra
• High cholesterol
• Acne vulgaris
• Osteoarthritis
• Reynaud's disease
• Schizophrenia
• Type 1 diabetes

Public Health Recommendations

In 1998, the National Academy of Sciences published Dietary Reference Intakes (DRIs) for vitamin B3. These DRIs included Adequate Intake (AI) levels for children under one year of age and Recommended Dietary Allowances (RDAs) for all other individuals. We have used the DRI for adult males as the standard for the nutrient charts on this page.These DRIs for vitamin B3 are listed below:.

• 0-6 months: 2 mg
• 6-12 months: 4 mg
• 1-3 years: 6 mg
• 4-8 years: 8 mg
• 9-13 years: 12 mg
• 14+ years, female: 14 mg
• 14 years, male: 16 mg
• Pregnant women: 18 mg
• Lactating women: 16 mg

The Daily Value (DV) for niacin intake that you will see referenced on food labels is 20 mg per 2000 calories.

As our recommended daily intake level for vitamin B3 at WHFoods, we chose the DRI for males ages 14 and older of 16 milligrams. All of our food rating charts use this level for calculating B3-richness in foods.

The DRIs also established Tolerable Upper Intake Levels (ULs) for vitamin B3. However, as reviewed earlier in the Risk of Dietary Toxicity section of this profile, the ULs for vitamin B3 do not apply to intake of this vitamin from whole, natural foods, but only to intake of B3 from dietary supplements and processed foods that have been fortified with additional B3 during processing. The ULs for intake of B3 from supplements and fortified foods (but not applicable to whole, natural foods) are as follows.

• 1-3 years: 10 milligrams
• 4-8 years: 15 milligrams
• 9-13 years: 20 milligrams
• 14-18 years: 30 milligrams
• 19 years and olders: 35 milligrams
• Pregnant or lactating women, 18 years and younger: 30 milligrams
• Pregnant or lactating women, 19 years and older: 35 milligrams

References

• Ersoy B, Ozeren A. The effect of cooking methods on mineral and vitamin contents of African catfish. Food Chem 2009;115:419-22.
• Food and Nutrition Board, Institute of Medicine. Dietary reference intakes for thiamin, riboflavin, niacin, vitamin B6, folate, vitamin B12, pantothenic acid, biotin, and choline. Washington, DC: National Academy Press; 1998;58-86.
• Janelle KC, Barr SI. Nutrient intakes and eating behavior scores of vegetarian and nonvegetarian women. J Am Diet Assoc 1995;95:180-6.
• Karmas E, Harris RS. Nutritional Evaluation of Food Processing. Springer, Netherlands, 1988.
• Lanska DJ. Chapter 30: historical aspects of the major neurological vitamin deficiency disorders: the water-soluble B vitamins. Handb Clin Neurol 2010;95:445-76.
• Le Floc'h N, Otten W, Merlot E. Tryptophan metabolism, from nutrition to potential therapeutic applications. Amino Acids 2011;41:1195-205.
• Leskova E, Kubikova J, Kovacikova E, et al. Vitamin losses: retention during heat treatment and continual changes expressed by mathematical models. J Food Comp Anal 2006;19:252-76.
• Nisha P, Singhal RS, Pandit AB. A study on degradation kinetics of niacin in potato (Solanum tuberosum L.). J Food Comp Anal 2009;22:620-4.
• Rajakumar K. Pellagra in the United States: a historical perspective. South Med J 2000;93:272-7.