The European food safety authority (EFSA) last evaluated vitamins and minerals for safety in 2006 and set a so-called Tolerable Upper Intake Level (UL) for each micronutrient, provided sufficient data were available. This UL reflects the safe maximum amount of a micronutrient that will not cause any side effects when taken daily from all sources over a lifetime.
The term niacin covers the compounds nicotinamide and nicotinic acid. Because of their different hazard potential, separate evaluation of nicotinamide and nicotinic acid is required.
| The maximum safe daily intake for nicotinamide is 900 mg. The maximum safe daily intake for nicotinamide is 56 times the EU recommended daily intake (Nutrient Reference Value, NRV). |
This value applies to adult men and women 19 years of age and older. It does not apply to pregnant and lactating women due to insufficient data.
Data from NVS II (National Nutrition Survey II, 2008) on the daily intake of niacin from all sources (conventional diet and supplements) suggest that an amount of 900 mg is far from being achieved.
No adverse side effects of excessive intakes of nicotinamide from diet and supplements have been observed to date.
The NOAEL (No Observed Adverse Effect Level) – the highest dose of a substance that has no detectable and measurable adverse effects even with continued intake – has been set by EFSA at 1,750 mg per day for nicotinamide. Accordingly, the dose at which no adverse effects were observed is twice the safe maximum daily intake.
Adverse effects of excessive nicotinamide intake (up to 3,000 mg nicotinamide per day) with food and supplements were, in very rare cases, gastrointestinal disturbances such as nausea (nausea) and, in isolated cases, hepatotoxic reactions (damage to the liver).
| The maximum safe daily intake for nicotinic acid is 10 mg. |
This value applies to adult men and women 19 years of age and older. It does not apply to pregnant women and nursing mothers due to insufficient data.
The LOAEL (Lowest Observed Adverse Effect Level) of nicotinic acid-the lowest dose of a substance at which adverse effects were just observed-was set by EFSA at 30 mg.
Adverse effects of high nicotinic acid intake at levels of 30 mg have been observed to include pruritus (itching), sensation of heat, flushing (sudden reddening of the skin) and, in some cases, urticaria (hives). In addition, such amounts of nicotinic acid may have a vasodilatory effect and affect blood clotting. Very high intakes of nicotinic acid (300 to over 3,000 mg per day) may cause nausea (nausea), vomiting, heartburn, diarrhea (diarrhea), and even abnormal liver values (increase in transaminases and/or alkaline phosphatase) and jaundice (jaundice).
However, it is not possible to ingest such amounts of nicotinic acid with food that could lead to undesirable side effects. Because nicotinamide can cause only mild side effects even in large amounts, it is often preferred to nicotinic acid. Nicotinamide is predominantly used in dietary supplements and fortified foods.
