Nicotinamide: benefits, dosage, contraindications
Other name(s)
Niacinamide, vitamin B3, vitamin PP
Scientific name(s)
Pyridine-3-carboxamide.
Family or group:
Vitamins
Indications
Scoring methodology
EFSA approval.
Vitamin B3 deficiency ✪✪✪✪✪
Nicotinamide is used for the prevention and treatment of niacin deficiency and pellagra (a condition primarily affecting the skin, with a painful erythema extending to areas exposed to light, sometimes accompanied by stomatitis and glossitis, and often severe physical and mental asthenia with delusional melancholy tending toward depression). Nicotinamide is sometimes preferred to niacin for this indication because it is better tolerated and does not have niacin's vasodilatory effects.
Posologie
Oral
500 - 1000 mg
Type 2 diabetes ✪✪✪✪✪
The intake of nicotinamide at a dose 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 patients with newly diagnosed type 1 diabetes. Nicotinamide has also been evaluated in adults with type 2 diabetes. A clinical study in lean patients with type 2 diabetes showed that taking niacinamide 500 mg three times a day for 6 months in combination with continuous insulin or sulfonylureas (a class of oral antidiabetic drugs) increases C-peptide release and improves insulin secretion compared with insulin alone.
Posologie
Oral
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 sulfonylureas
A multi-center 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 the application of 4% nicotinamide gel twice daily for 8 weeks is as effective as 1% clindamycin gel in reducing the number and severity of acne lesions. Nicotinamide appears to be 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
Topical
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 daily 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 with placebo. Other 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 odds of developing at least one non-melanoma skin cancer by 86% compared with placebo.
Posologie
Oral
500 - 1000 mg
12 months
Osteoarthritis ✪✪✪✪✪
Clinical research in patients with osteoarthritis shows that taking 3 grams of nicotinamide per day, in six divided doses, for 12 weeks, reduces joint inflammation and decreases the use of nonsteroidal anti-inflammatory drugs compared with placebo.
Posologie
Oral administration
3 g
12 - weeks
Eczema ✪✪✪✪✪
A small clinical study in patients with atopic dermatitis and dry skin shows that the application of 2% nicotinamide cream twice daily for 8 weeks reduces transepidermal water loss and improves skin hydration compared with the use of a petrolatum-based moisturizer.
Posologie
Topical application
8 - weeks
Properties
Neurological
Nicotinamide plays a role in the cytoprotection of brain cells. Several mechanisms of action have been proposed in the literature. For example, nicotinamide supplementation increases NADPH levels, which protect cells from the toxicity of reactive oxygen species. In animal models of ischemia/reperfusion, nicotinamide prevents brain injury by reducing neuronal death. In other animal models, it prevents apoptosis of neurons and endothelial cells induced by anoxia or nitric oxide. Thus, high doses of nicotinamide appear to protect against various neurological diseases, notably 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 plaques) and atopic dermatitis, possibly through its anti-inflammatory effects. In addition, nicotinamide reduces UV-induced damage by decreasing skin inflammation. On the other hand, nicotinamide has anti-aging effects. Indeed, it increases skin hydration by raising 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 appears to increase activation of p53, a protein involved in regulation of the cell cycle and tumor suppression. Furthermore, the use of nicotinamide as an adjuvant to cancer treatment has been proposed. It is thought that the hypoxic environment in which tumor cells reside causes tumor resistance to radiotherapy. Nicotinamide administered at the time of tumor irradiation, known as accelerated radiotherapy with carbogen and nicotinamide, increases local tumor control by increasing blood flow and oxygen delivery to the tumors.
Usages associés
Anti-inflammatory
Treatment with nicotinamide decreases the expression of pro-inflammatory cytokines in cultured cells and in mice and also reduces superoxide generation in activated neutrophils and monocytes. Nicotinamide appears to inhibit the induction of nitric oxide synthase (an enzyme that produces nitric oxide) by interleukin-1 in chondrocytes (cartilage cells), thereby reducing inflammation and leading researchers to consider its potential role in destructive joint diseases.
Usages associés
Immunomodulatory
Nicotinamide inhibits proliferation and the secretion of immunoglobulins by primary B cells. In addition, it appears to be of interest in antibody-dependent autoimmune diseases or in conditions of heightened immune response such as toxic shock induced by a bacterial enterotoxin. For example, nicotinamide attenuates the expression of MHC class II (major histocompatibility complex class II: molecule found on the surface of antigen-presenting cells) and the proliferation of T cells induced by staphylococcal enterotoxin.
Hypoglycemic
Nicotinamide can protect or improve beta cell function and increase insulin secretion. In vitro, it prevents or delays insulin deficiency in type 1 diabetes models.nnThe mechanisms of beta cell protection by nicotinamide may include inhibition of poly(ADP-ribose) polymerase, which is activated during toxin-induced beta cell injury, scavenging of reactive oxygen species and nitric oxide. Mechanisms may also include restoration of intracellular NAD pools, alteration of autoimmune processes, including reduction of class II major histocompatibility complex expression and blockade of the effects of interleukin-1.nn
Usages associés
Antidepressant
Nicotinamide appears to work largely by increasing the synthesis and decreasing the breakdown 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. Increasing serotonin levels at the synapses is the major mechanism of action of antidepressants. This suggests that increasing NAD+ supply via the salvage pathway, rather than by de novo synthesis from tryptophan, would help cells by increasing the availability of tryptophan for serotonin production.nn
Anti-aging
Cellular NAD+ levels decrease with aging, with a similar reduction in the activity level of Sirtuin 1 (a protein whose expression is reduced in cells that have high insulin resistance, and induction of its expression increases insulin sensitivity). This may contribute to the development of age-associated diseases as well as to the acceleration of related degeneration. Consequently, nicotinamide appears to be useful in many diseases and conditions related to aging. In vitro, nicotinamide considerably extends the cellular lifespan of human fibroblasts in culture, keratinocytes, and bone marrow stem cells, which have a limited replicative lifespan.
Safe dosage
Infant from 7 to 11 months: 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 therefore expressed in mg NE / MJ. Values expressed in mg NE / day can be calculated based on the energy requirements of the group concerned.
Child from 1 to 3 years: 1.6 mg
The values refer 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 linked to energy requirements and are therefore expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy requirements of the group concerned. nn
Child aged 1 to 3 years: 150 mg (nicotinamide)
The values refer 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 linked to energy requirements and are therefore expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy requirements of the group concerned. nn
Child aged 4 to 6 years: 1.6 mg
The values refer 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 linked to energy requirements and are therefore expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy requirements of the group concerned. nn
Child aged 4 to 6 years: 220 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 requirements and are therefore expressed in mg NE / MJ. Values expressed in mg NE / day can be calculated based on the energy requirements of the group considered.
Child aged 7 to 10 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 requirements and are therefore expressed in mg NE / MJ. Values expressed in mg NE / day can be calculated based on the energy requirements of the group considered.
Child aged 7 to 10 years: 350 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 requirements and are therefore expressed in mg NE / MJ. Values expressed in mg NE / day can be calculated based on the energy requirements of the group considered.
Child aged 11 to 14 years: 1.6 mg
The values refer 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 requirements and are therefore expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy requirements of the group concerned.
Child aged 11 to 14 years: 500 mg (nicotinamide)
The values refer 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 requirements and are therefore expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy requirements of the group concerned.
Child aged 15 to 17 years: 1.6 mg
The values refer 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 requirements and are therefore expressed in mg NE/MJ. Values expressed in mg NE/day can be calculated based on the energy requirements of the group concerned.
Child aged 15 to 17 years: 700 mg (nicotinamide)
The values refer 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 requirements and are therefore expressed in mg NE / MJ. Values expressed in mg NE / day can be calculated based on the energy requirements of the group considered. nn
Adults aged 18 years and over: 1.6 mg
The values refer 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 requirements and are therefore expressed in mg NE / MJ. Values expressed in mg NE / day can be calculated based on the energy requirements of the group considered. nn
Adults aged 18 years and over: 900 mg (nicotinamide)
The values refer 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 requirements and are therefore expressed in mg NE / MJ. Values expressed in mg NE / day can be calculated based on the energy requirements of the group considered. nn
Breastfeeding women aged 18 years and over: 1.6 mg
The values refer 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 requirements and are therefore expressed in mg NE / MJ. Values expressed in mg NE / day can be calculated according to the energy requirements of the group concerned.nn
Pregnant women aged 18 years and older: 1.6 mg
The values refer 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 requirements and are therefore expressed in mg NE / MJ. Values expressed in mg NE / day can be calculated according to the energy requirements of the group concerned.nn
Interactions
Médicaments
Antiplatelet agents/Anticoagulants: moderate interaction
Theoretically, nicotinamide may have additive effects when used with anticoagulants or antiplatelet agents, particularly in patients undergoing hemodialysis.
Carbamazepine: moderate interaction
Nicotinamide may increase the levels and adverse effects of carbamazepine.
Precautions
Renal insufficiency: use with caution
Nicotinamide supplementation appears to increase the risk of thrombocytopenia compared with placebo in patients undergoing hemodialysis.nn
