nicotinamide: benefits, dosage, contraindications
Other name(s)
niacinamide, vitamin B3, vitamin PP
Scientific name(s)
Pyridine-3-carboxamide.
Family or group:
Vitamins
Indications
Rating methodology
EFSA approval.
Vitamin B3 Deficiency ✪✪✪✪✪
Nicotinamide is used for the prevention and treatment of niacin deficiency and pellagra (primarily a skin condition with extensive painful erythema on light-exposed areas, sometimes accompanied by stomatitis and glossitis, and often intense physical and psychological asthenia with melancholic delusion and depressive tendency). Nicotinamide is sometimes preferred over niacin for this indication because it is better tolerated and lacks the vasodilatory effects of niacin.
Posologie
Orally
500 - 1000 mg
Type 2 Diabetes ✪✪✪✪✪
Taking nicotinamide at a rate of 1.2 grams/m2 per day for 5 years may prevent the loss of beta cell function in children with type 1 diabetes. Indeed, there is evidence showing that nicotinamide can preserve residual beta cell function in newly diagnosed type 1 diabetes patients. Nicotinamide has also been evaluated in adults with type 2 diabetes. A clinical study in lean type 2 diabetic patients shows that taking niacinamide 500 mg three times daily for 6 months in combination with continuous insulin or sulfonylureas (a class of oral antidiabetic) increases C-peptide release and improves insulin secretion compared to insulin alone.
Posologie
Orally
1.2 g/m²
5 - years
Effect of nicotinamide on newly diagnosed type 1 diabetic children
Meta-analysis of nicotinamide treatment in patients with recent-onset IDDM. The Nicotinamide Trialists
Vitamin E and nicotinamide have similar effects in maintaining residual beta cell function in recent onset insulin-dependent diabetes (the IMDIAB IV study)
Nicotinamide improves insulin secretion and metabolic control in lean type 2 diabetic patients with secondary failure to sulphonylureas
A multi-centre randomized trial of two different doses of nicotinamide in patients with recent-onset type 1 diabetes (the IMDIAB VI)
Acne ✪✪✪✪✪
A clinical study shows that applying 4% nicotinamide gel twice daily for 8 weeks is as effective as 1% clindamycin gel in reducing the number and severity of acne lesions. Niacinamide seems more effective in patients with oily skin. Other preliminary clinical research has reported that oral nicotinamide improves acne when used in combination with zinc, copper, and folic acid.
Posologie
Topically
Synergies
Skin Cancer ✪✪✪✪✪
A clinical study in patients with a history of non-melanoma skin cancers shows that taking 500 mg of oral nicotinamide twice a day for 12 months reduces the rate of new non-melanoma skin cancers by 23% and the number of actinic keratoses (a marker of excessive sun exposure and skin cancer risk) by 13%, compared to placebo. Further clinical research shows that taking 500 mg of oral nicotinamide once or twice daily for 4 months reduces the total number of actinic keratoses by up to 35% and decreases the chances of developing at least one non-melanoma skin cancer by 86% compared to placebo.
Posologie
Orally
500 - 1000 mg
12 - months
Arthritis ✪✪✪✪✪
Clinical research in patients with arthritis shows that taking 3 grams of nicotinamide per day, in six divided doses, for 12 weeks, reduces joint inflammation and decreases the use of non-steroidal anti-inflammatory drugs compared to placebo.
Posologie
Orally
3 g
12 - weeks
Eczema ✪✪✪✪✪
A small clinical study in patients with atopic dermatitis and dry skin shows that applying 2% nicotinamide cream twice daily for 8 weeks decreases transepidermal water loss and improves skin hydration compared to using a petroleum jelly-based moisturizer.
Posologie
Topically
8 - weeks
Properties
Neurological
Nicotinamide plays a role in the cytoprotection of brain cells. Various mechanisms of action have been proposed in the literature. For instance, nicotinamide supplementation increases the level of NADPH which protects cells from the toxicity of reactive oxygen species. In animal models of ischemia/reperfusion, nicotinamide prevents brain damage by improving neuronal death. In other animal models, it prevents the apoptosis of neurons and endothelial cells induced by anoxia or nitric oxide. Thus, high doses of nicotinamide seem to protect against various neurological diseases, including Alzheimer's disease, Huntington's disease, Parkinson's disease, and multiple sclerosis.
Dermatological Effect
Nicotinamide appears to improve inflammatory and autoimmune skin diseases such as acne vulgaris, bullous pemphigoid (a skin disease characterized by the appearance of large blisters on red patches) and atopic dermatitis, possibly due to its anti-inflammatory effects. Furthermore, nicotinamide reduces damage caused by UV radiation by decreasing skin inflammation. Moreover, nicotinamide has anti-aging effects. Indeed, it increases skin hydration by boosting levels of sphingolipids (complex lipids derived from the sphingosine molecule), free fatty acids, and cholesterol, key components of the skin barrier. Clinical research also suggests that niacinamide reduces skin pigmentation.
Usages associés
Anticancer
In vitro, nicotinamide seems to increase the activation of p53, a protein involved in cell cycle regulation and tumor suppression. Furthermore, the use of nicotinamide as an adjunct to cancer treatment has been proposed. It is believed that the hypoxic environment in which tumor cells reside causes tumor resistance to radiation therapy. Nicotinamide administered at the time of tumor radiation, called accelerated radiotherapy with carbogen and nicotinamide, increases local tumor control by accelerating blood flow and oxygen delivery to tumors.
Usages associés
Anti-inflammatory
Treatment with nicotinamide decreases the expression of pro-inflammatory cytokines in cultured cells and mice and also reduces superoxide generation in activated neutrophils and monocytes. Niacinamide seems to inhibit the induction of nitric oxide synthase (an enzyme that produces nitric oxide) by interleukin-1, at the level of chondrocytes (cartilage cells), thus reducing inflammation and leading researchers to think of its potential role in destructive joint diseases.
Usages associés
Immuno-modulator
Nicotinamide inhibits the proliferation and secretion of immunoglobulins by primary B cells. Moreover, it seems interesting in antibody-dependent autoimmune diseases or conditions of heightened immune response such as a toxic shock induced by bacterial enterotoxin. For example, nicotinamide attenuates the expression of class II MHC (major histocompatibility complex class II: a molecule found on the surface of antigen-presenting cells) and the proliferation of T cells induced by staphylococcal enterotoxin.
Hypoglycemic
Nicotinamide may protect or improve beta cell function and increase insulin secretion. In vitro, it prevents or delays insulin deficiency in type 1 diabetes models. The mechanisms for beta cell protection by nicotinamide may include the inhibition of poly (ADP-ribose) polymerase which is activated during toxin-induced beta cell damage, free oxygen radical scavenging, and nitric oxide. Mechanisms may also include the restoration of intracellular NAD pools, alteration of autoimmune processes, including a reduction in class II major histocompatibility complex expression and blocking the effects of interleukin-1.
Usages associés
Antidepressant
Nicotinamide seems to work largely by increasing the synthesis and decreasing the degradation of monoamine neurotransmitters, including serotonin. Indeed, tryptophan, a precursor of NAD + in the de novo pathway, is also a precursor of monoamine neurotransmitters, including serotonin, which regulates mood, appetite, and sleep. The increase in serotonin levels at synapses is the major action mechanism of antidepressants. This suggests that increasing NAD + supply via the salvage pathway, rather than de novo synthesis from tryptophan, would help cells by increasing the availability of tryptophan for serotonin production.
Anti-aging
The cellular level of NAD + decreases with aging with a similar decrease in the activity level of Sirtuin 1 (a protein whose expression is decreased in cells with high insulin resistance and induction of its expression enhances insulin sensitivity). This can contribute to the development of aging-associated diseases and acceleration of associated degeneration. Consequently, nicotinamide seems useful in many aging-related diseases and conditions. In vitro, nicotinamide significantly extends the cellular lifespan of cultured human fibroblasts, keratinocytes, and bone marrow stem cells, which have limited replicative lifespan.
Safety dosage
Infant aged 7 to 11 months: 1.6 mg
The values relate to niacin as nicotinamide and nicotinic acid. Niacin can be synthesized in the human body from tryptophan, an essential amino acid. NE: niacin equivalent (1 NE = 1 mg niacin = 60 mg dietary tryptophan). Niacin needs are related to energy needs and thus expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy needs of the respective group.
Child aged 1 to 3 years: 1.6 mg
The values relate to niacin as nicotinamide and nicotinic acid. Niacin can be synthesized in the human body from tryptophan, an essential amino acid. NE: niacin equivalent (1 NE = 1 mg niacin = 60 mg dietary tryptophan). Niacin needs are related to energy needs and thus expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy needs of the respective group.
Child aged 1 to 3 years: 150 mg (nicotinamide)
The values relate to niacin as nicotinamide and nicotinic acid. Niacin can be synthesized in the human body from tryptophan, an essential amino acid. NE: niacin equivalent (1 NE = 1 mg niacin = 60 mg dietary tryptophan). Niacin needs are related to energy needs and thus expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy needs of the respective group.
Child aged 4 to 6 years: 1.6 mg
The values relate to niacin as nicotinamide and nicotinic acid. Niacin can be synthesized in the human body from tryptophan, an essential amino acid. NE: niacin equivalent (1 NE = 1 mg niacin = 60 mg dietary tryptophan). Niacin needs are related to energy needs and thus expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy needs of the respective group.
Child aged 4 to 6 years: 220 mg (nicotinamide)
The values relate to niacin as nicotinamide and nicotinic acid. Niacin can be synthesized in the human body from tryptophan, an essential amino acid. NE: niacin equivalent (1 NE = 1 mg niacin = 60 mg dietary tryptophan). Niacin needs are related to energy needs and thus expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy needs of the respective group.
Child aged 7 to 10 years: 1.6 mg
The values relate to niacin as nicotinamide and nicotinic acid. Niacin can be synthesized in the human body from tryptophan, an essential amino acid. NE: niacin equivalent (1 NE = 1 mg niacin = 60 mg dietary tryptophan). Niacin needs are related to energy needs and thus expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy needs of the respective group.
Child aged 7 to 10 years: 350 mg (nicotinamide)
The values relate to niacin as nicotinamide and nicotinic acid. Niacin can be synthesized in the human body from tryptophan, an essential amino acid. NE: niacin equivalent (1 NE = 1 mg niacin = 60 mg dietary tryptophan). Niacin needs are related to energy needs and thus expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy needs of the respective group.
Child aged 11 to 14 years: 1.6 mg
The values relate to niacin as nicotinamide and nicotinic acid. Niacin can be synthesized in the human body from tryptophan, an essential amino acid. NE: niacin equivalent (1 NE = 1 mg niacin = 60 mg dietary tryptophan). Niacin needs are related to energy needs and thus expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy needs of the respective group.
Child aged 11 to 14 years: 500 mg (nicotinamide)
The values relate to niacin as nicotinamide and nicotinic acid. Niacin can be synthesized in the human body from tryptophan, an essential amino acid. NE: niacin equivalent (1 NE = 1 mg niacin = 60 mg dietary tryptophan). Niacin needs are related to energy needs and thus expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy needs of the respective group.
Child aged 15 to 17 years: 1.6 mg
The values relate to niacin as nicotinamide and nicotinic acid. Niacin can be synthesized in the human body from tryptophan, an essential amino acid. NE: niacin equivalent (1 NE = 1 mg niacin = 60 mg dietary tryptophan). Niacin needs are related to energy needs and thus expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy needs of the respective group.
Child aged 15 to 17 years: 700 mg (nicotinamide)
The values relate to niacin as nicotinamide and nicotinic acid. Niacin can be synthesized in the human body from tryptophan, an essential amino acid. NE: niacin equivalent (1 NE = 1 mg niacin = 60 mg dietary tryptophan). Niacin needs are related to energy needs and thus expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy needs of the respective group.
Adult over 18 years: 1.6 mg
The values relate to niacin in the form of nicotinamide and nicotinic acid. Niacin can be synthesized in the human body from tryptophan, an essential amino acid. NE: niacin equivalent (1 NE = 1 mg niacin = 60 mg dietary tryptophan). Niacin requirements are related to energy needs and are thus expressed in mg NE / MJ. Values expressed in mg NE / day can be calculated based on the energy needs of the specific group considered.
Adult from 18 years: 900 mg (nicotinamide)
The values relate to niacin in the form of nicotinamide and nicotinic acid. Niacin can be synthesized in the human body from tryptophan, an essential amino acid. NE: niacin equivalent (1 NE = 1 mg niacin = 60 mg dietary tryptophan). Niacin requirements are related to energy needs and are thus expressed in mg NE / MJ. Values expressed in mg NE / day can be calculated based on the energy needs of the specific group considered.
Lactating woman from 18 years: 1.6 mg
The values relate to niacin in the form of nicotinamide and nicotinic acid. Niacin can be synthesized in the human body from tryptophan, an essential amino acid. NE: niacin equivalent (1 NE = 1 mg niacin = 60 mg dietary tryptophan). Niacin requirements are related to energy needs and are thus expressed in mg NE / MJ. Values expressed in mg NE / day can be calculated based on the energy needs of the specific group considered.
Pregnant woman from 18 years: 1.6 mg
The values relate to niacin in the form of nicotinamide and nicotinic acid. Niacin can be synthesized in the human body from tryptophan, an essential amino acid. NE: niacin equivalent (1 NE = 1 mg niacin = 60 mg dietary tryptophan). Niacin requirements are related to energy needs and are thus expressed in mg NE / MJ. Values expressed in mg NE / day can be calculated based on the energy needs of the specific group considered.
Interactions
Médicaments
Antiplatelet/Anticoagulant: moderate interaction
Theoretically, nicotinamide may have additive effects when used with anticoagulants or antiplatelet agents, especially in patients undergoing hemodialysis.
Carbamazepine: moderate interaction
Nicotinamide may increase levels and adverse effects of carbamazepine.
Precautions
Renal insufficiency: use with caution
Supplementation with nicotinamide appears to increase the risk of thrombocytopenia compared to placebo, in patients undergoing hemodialysis.
