Suicidal thoughts may be linked to vitamin B3 deficiency

According to a study published in BMC Psychiatry, increasing one’s intake of vitamin B3 may improve mood and reduce or even eliminate suicidal thoughts. It is important to note, however, that vitamin B3 is primarily found in protein-rich foods, and a plant-based diet may increase the risk of deficiency. Additionally, stimulants, genetic factors, and aging can make it harder to utilize B3 from the diet, because B3 must first be converted into its active form, NAD, which is important for energy metabolism, mood, and mental balance.

Worldwide, suicide causes more than 700,000 deaths each year. As a result, the World Health Organization has set a goal of reducing suicide rates in every country by 33 percent between 2013 and 2030. Suicidal thoughts include both serious considerations of suicide and actual suicide attempts. It is estimated that around 1.4 percent of psychiatric patients with severe suicidal thoughts die by suicide within a year. Therefore, it is highly relevant to identify all factors that increase the risk of suicidal thoughts, as this can help improve prevention efforts.
It is well known that personal problems, trauma, and other mental health factors may be associated with suicidal thoughts. In addition, an unhealthy diet and deficiencies in specific nutrients can affect the nervous system, increasing vulnerability to mental health issues. Several studies have shown that low blood sugar, as well as deficiencies in vitamin D, B3, folate, vitamin B12, and zinc, may contribute to depression and other psychiatric disorders. However, the specific relationship between B3 and suicidal thoughts has not been well understood. The new study aimed to examine this relationship in more detail.
Researchers analyzed data from 26,224 Americans who participated in the large, long-term population study NHANES. Participants’ B3 intake was assessed twice, using a comprehensive dietary questionnaire and telephone interviews. The researchers also looked at whether there was a connection between B3 intake and the inflammation marker CRP (C-reactive protein), because brain inflammation can affect the nervous system and mood.
The study found that 970 participants (3.7%) reported suicidal thoughts. Also, the researchers found a significant inverse relationship between B3 intake and the occurrence of suicidal thoughts: in other words, lower B3 intake was associated with a higher risk of suicidal thoughts. This relationship remained significant even after adjusting for various confounding factors.
Subgroup analyses showed that the association between B3 deficiency and suicidal thoughts was stronger among participants with hyperlipidemia, which is characterized by elevated blood lipids. This condition is more common in people with metabolic syndrome, a precursor to type 2 diabetes.
The study indicated that a daily intake of 26.78 mg of B3 was associated with the most positive effects on mood and suicidal thoughts, as well as on CRP levels. Researchers concluded that higher intake of B3 is associated with a reduced risk of suicidal thoughts and emphasized the importance of sufficient B3 intake for public mental health.

• Vitamin B3 is found in protein-rich foods such as meat, fish, eggs, nuts, whole grains, and legumes.
• It is estimated that 1.7 billion people worldwide are deficient in vitamin B3.

Vitamin B3 and its role in energy, the nervous system, and mood

Vitamin B3 (niacin) refers to nicotinic acid and nicotinamide, which are present in food and supplements. According to the study’s introduction, B3 plays a role in:

• Cellular energy metabolism
• The development and function of nerve cells, important for normal central nervous system function and mental balance
• Acting as an antioxidant that protects cells - including nerve cells - from damage caused by free radicals and oxidative stress
• Potentially reducing aging processes as an antioxidant
• May protect nerve cells as an antioxidant
• Reducing CRP, a marker of chronic inflammation often involved in depression

Disruptions in B3 metabolism may lead to imbalances in physiological processes, potentially contributing to various psychiatric conditions. B3 metabolism is complex: when B3 participates in energy metabolism, it is converted into its active form, NAD (nicotinamide adenine dinucleotide). NAD, which is present in all living cells, accepts and donates electrons, which enables it to cycle between NAD+ and NADH. This makes it possible for cells to produce concentrated chemical energy as ATP. NAD is also involved in hundreds of coenzymes, including those needed for serotonin production and calcium signaling in cells. Serotonin is widely known to influence mood, and proper calcium signaling is critical for nerve cell function. Dysregulation can lead to cellular stress and excitotoxicity.

Official recommendations, individual needs, and supplementation

The official recommended daily intake of vitamin B3 for adults is 16 mg. This amount prevents the classical deficiency disease pellagra. However, according to the new study, 27 mg may be more relevant in relation to mood. Vitamin B3 deficiency being so common, this poses a problem. First, B3 deficiency can result from a limited or unbalanced diet. Second, alcohol abuse, excessive coffee consumption, diuretics, liver disease, and certain gastrointestinal conditions can increase the body’s requirement for B3. Third, aging processes and genetic variations in cellular DNA can make it more difficult for some people to convert and utilize B3 into its active form, NAD. This means that many people actually have an increased need for B3, especially if there are issues with cellular energy metabolism or the nervous system.
Regarding B3 supplementation, nicotinic acid enters the bloodstream fastest and generally has a stronger therapeutic effect than nicotinamide. Because higher doses of nicotinic acid can cause harmless facial flushing and warmth (“niacin flush”), it is recommended to start with low doses and gradually increase to higher therapeutic doses, which should be spread throughout the day.
There are also very strong B3 supplements on the market, such as NAD+ boosters (with daily doses of 500 mg or more), which contain both nicotinic acid and nicotinamide in a slow-release formula. This provides a more stable release over an extended period.
However, pregnant women should not take high doses of niacin (over 35 mg per day), as it may harm the fetus.
People with ulcers, arterial bleeding, or liver disease should also avoid taking high doses of vitamin B3.

• The diet’s role in mental health is often overlooked in psychiatry
• Vitamin B3 is of key importance to cellular energy turnover and the nervous system
• A plant-based diet increases the risk of becoming vitamin B3-deficient
• Stimulant abuse, ageing, and genetic factors can make it difficult for some people to utilize vitamin B3 from the diet and from supplements

References:

Hao Lin et al. Association between dietary niacin intake and suicidal intention: mediating role of C-reactive protein. BMC Psychiatry 2025

Soraya Djadjo, Tushar Bajaj. Niacin. StatPearls (Internet) 2023

Simone Passarelli et al. Global estimation of dietary micronutrient inadequacies: a modeling analysis. The Lancet Global Health 2024