Niacin, also known as vitamin B3, helps release energy from the foods we eat by acting as coenzyme in energy-transfer reactions, especially the metabolism of glucose, fat, and alcohol. Niacin also helps keep the nervous system and skin healthy. There are two forms of niacin – nicotinic acid and nicotinamide – both of which are found in food. Niacin is unique in that it can also be synthesized from the amino acid tryptophan.
The Primary Sources of Vitamin B3
Primary sources are offal (liver), fish, meat, milk, eggs, whole grain cereals, legumes, fruit (avocados, figs, dates, prunes), and nuts. Vitamin B3 can also be synthesized from tryptophan.
Bioavailability of Vitamin B3
Absorption of niacin depends on the food source. Niacin from meat, liver, beans and fortifed products is highly bioavailable. About 30% of the niacin in grains is bioavailable, though additional niacin can be released if the food undergoes alkali treatment (limewater/calcium hydroxide).
Compared to other water-soluble vitamins, niacin is less susceptible to losses during food storage. It is fairly heat resistant, so it can withstand reasonable cooking times. However, like other water-soluble vitamins, it will leach into cooking water.
Risks Related to Inadequate or Excess Intake of Vitamin B3
Individuals whose diets to not meet their energy needs are therefore at risk of deficiency, as are individuals whose staple diet relies primarily on (untreated) maize or barley, and chronic alcoholics. Severe niacin deficiency results in a disease called pellagra and its symptoms are dermatitis, diarrhea, dementia and eventually death.
Risk of excessive intake is unlikely if niacin is consumed from food sources. However, consumption of niacin in the form of nicotinic acid from multiple sources at high levels, including dietary supplements, pharmaceutical doses, and fortifed foods, may result in adverse effects such as flushing, nausea and vomiting, liver toxicity, blurred vision and impaired glucose tolerance.
Incorporate vitamin B3 into your morning routine with this A perfect breakfast recipe below.
Baked Eggs with Tomatoes, Chorizo, Chilli and Cheese*
2 tablespoons olive oil
4 large ripe tomatoes, skinned, seeded and chopped
2 tablespoons chopped parsley
A good pinch of crushed chilli peppers (dried chilli pepper flakes)
8 large eggs
8 slices of chorizo
50g (2oz) manchego or Parmesan, grated
4 slices of bread, toasted and buttered, to serve
Preheat the oven to 180°C, 350°F, Gas 4. Put a frying pan on a medium-low heat, add the olive oil then add the skinned, chopped tomatoes, see my tip, above left. Season with a good pinch of salt and cook for about 15 minutes, until the tomato sauce is thick and viscous.
Remove from the heat, stir in the chopped parsley and the crushed chilli peppers. Divide the tomato sauce between four ovenproof ramekins and break 2 eggs into each dish. Place a slice of the chorizo on top of each egg and divide the grated manchego or Parmesan cheese, whichever you’re using, between the ramekins.
Place in the preheated oven and bake for 10-15 minutes, until the whites are set, but the yolks are just ever so slightly soft. Just before the eggs are ready, toast the slices of bread and butter them.
Remove the eggs from the oven and serve with the buttered toast.