Dr C P Ravikumar

Niacin or Vitamin B3 is known to regulate and help with several important functions of the body, including cell growth and repair, and the development and protection of the body’s nervous system. Research is ongoing to determine the benefits of niacin in alleviating the symptoms of neuro-degenerative disorders like Alzheimer’s Disease, Parkinson’s Disease or migraines.
Required Daily amount
The daily recommended dietary allowances (RDAs) of  Niacin are:

Age Male Female Pregnancy Lactation
0 – 6 months 2 mg 2 mg
7 – 12 months 4 mg NE 4 mg NE
1 – 3 years 6 mg NE 6 mg NE
4 – 8 years 8 mg NE 8 mg NE
9 – 13 years 12 mg NE 12 mg NE
14 – 18 years 16 mg NE 14 mg NE 18 mg NE 17 mg NE
19+ 16 mg NE 14 mg NE 18 mg NE 17 mg NE

(NE= Niacin Equivalents) Sources of Niacin Natural Sources of Vitamin B3 Niacin is a type of Vitamin B that is present in:
  • Meat
  • fish,
  • poultry
  • peanuts
  • cereals
  • whole grains
In India, Niacin- rich foods include:
  • custard apple,
  • mangoes,
  • dates
  • figs,
  • moong dal,
  • bajra,
  • sesame seeds
  • sunflower seeds

Supplements of Vitamin
In most countries, cereals are fortified with nicotinic acid as well as other nutrients in order to make sure people receive their daily requirements. Supplements are available as oral multi-vitamins or vitamin B complexes.

Causes of Niacin Deficiency
  • inadequate intake of nutritious, whole some food, which may occur in some developing countries.
  • if an individual has trouble absorbing nutrients from food in the intestine (malabsorption syndromes) or concurrent liver diseases, which makes assimilation and metabolism of nicotinamide, difficult.
  • In adolescents, anorexia nervosa may also cause decreased intake of several nutrients.
  • In areas where corn or cornmeal is the staple diet, occurrence of niacin deficiency is known, as corn is very poor in vitamin b3.
  • Some patients who are on long term anti-tuberculous medications are also known to develop nutrient deficiencies.
  • Destruction of Niacin: Being a water-soluble vitamin, heating, preserving or boiling of food in which it is present, may also deplete resources from the diet. 

Health Benefits of Niacin
There are studies that indicate the use of nicotinic acid supplementation to improve lipid levels in blood , however there is not sufficient evidence to show  significant effects on risk of cardiovascular events. Using Niacin as a drug to supplement treatment of hyperlipidaemia ,should  only be done under medical supervision.

Side effects of Excessive Niacin Intake
No adverse events usually occur due to intake of niacin from naturally occurring sources in food. However, niacin taken in extremely high doses as supplements or medications may cause:
  • Skin flushing (reddish color on patient’s arms, face and chest due to dilation of blood vessels under the skin), which may be accompanied by burning, tingling or itching.
  • Headaches
  • Rashes
  • Dizziness
  • Fluctuation in blood pressure
  • Hepatotoxic (harmful to the liver) due to long term excessive use as a supplement or medication

Therefore, the Food and Nutrition Board (UK) has established upper limits for supplementation with niacin:
Symptoms of Niacin Deficiency
The most common symptoms of niacin deficiency present as a triad of diarrhea, dermatitis and dementia, collectively called pellagra or “the three D disease”.
  1. Dermatitis involves a scaly rash with red flaky skin, areas of discoloration and itchy burning patches of skin. Rash around the neck is distinctive and is known as the “Casal Necklace”.
  2. Diarrhea may be persistent and accompanied by nausea and vomiting.
  3. Dementia includes neurological symptoms like depression, anxiety, irritability and mood swings. Children may present with history of low concentration, confusion or delusions.

Diagnosis of Niacin Deficiency  
Blood tests are available to detect low levels of niacin in the body, along with NAD  and NADP levels and their ratio,  for Nicotinamide nucleotide metabolism.
Checking the urine for by products of niacin metabolism, also indicates whether the quantity of vitamin B3 present in the body is adequate or not.
Management of Niacin Deficiency  
Dietary changes along with niacin supplements either orally or intravenously help to treat the symptoms of pellagra. However, concurrent issues with absorption of nutrients from the intestine or liver disorders also need to be treated in order to deal with the underlying cause. Nerve disorders may require consultation with a child neurologist to deal with symptoms appropriately. Optimal dietary intake of vitamin B has shown benefits in neuronal health and may delay neurodegeneration.
In cases of nutritional deficiency causing neurological symptoms especially in children, it is imperative to diagnose and intervene at the earliest. Although supplementing diets can help, long term nervous system disorders require guidance from clinical neurologists trained in paediatric care. Children will also benefit from multi-disciplinary care, including dieticians, psychiatrists and clinicians for holistic improvement .

Disclaimer: The above information is for awareness and education purposes only and cannot be used for diagnosis or treatment of any condition. Please consult with a physician for any concerns or questions

References:  
  1. Gasperi V, Sibilano M, Savini I, Catani MV. Niacin in the Central Nervous System: An Update of Biological Aspects and Clinical Applications. Int J Mol Sci. 2019;20(4):974. Published 2019 Feb 23. doi:10.3390/ijms20040974
  2. Redzic S, Gupta V. Niacin Deficiency. [Updated 2020 May 31]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK557728/
  3. https://ods.od.nih.gov/factsheets/Niacin-HealthProfessional/
Picture of Dr C P Ravikumar

Dr C P Ravikumar

CONSULTANT – PEDIATRIC NEUROLOGY
Aster CMI Hospital, Bangalore