Next in our tour of the B vitamins is vitamin B6, also called pyridoxine. If thiamine, riboflavin, and niacin are mainly about energy, B6 is the one most closely tied to protein — and to the brain. It is involved in well over a hundred enzyme reactions, and it touches everything from your mood to your blood.

What Vitamin B6 Does

Vitamin B6 is a remarkably versatile coenzyme. Its most important roles include:

• Protein metabolism: B6 is central to breaking down and using the amino acids from the protein you eat — the more protein in your diet, the more B6 you need.
• Brain chemistry: it helps make neurotransmitters such as serotonin and dopamine, the chemical messengers that influence mood, sleep, and focus.
• Red blood cells: B6 is needed to make hemoglobin, the protein that carries oxygen in the blood.
• Immune function: it supports a healthy immune response.
• Heart health: together with folate and B12, it helps keep levels of a substance called homocysteine in a healthy range.

B6, Protein, and the Brain

Because B6 is so involved in handling amino acids, it sits right at the meeting point of two themes from this series: protein and vitamins working as a team. The protein you eat provides the raw amino acids, and B6 provides the tool that lets the body rearrange them — including turning certain amino acids into the brain chemicals that affect how you feel. This connection to mood and the nervous system is one reason B6 receives so much attention.

Where to Find Vitamin B6

Vitamin B6 is found in a wide variety of everyday foods, which makes it easy to obtain. Good sources include:

• Poultry and fish such as chicken, turkey, tuna, and salmon.
• Potatoes and other starchy vegetables.
• Bananas, one of the best-known fruit sources.
• Chickpeas and other legumes.
• Nuts, seeds, and fortified cereals.

Like the other B vitamins, B6 is water-soluble, so a steady supply from food is best. It is reasonably widespread, so deficiency is uncommon in people eating a balanced diet, though it can occur alongside shortages of other B vitamins. As with niacin, it is worth knowing that very high-dose B6 supplements taken over long periods can actually cause nerve problems — a clear case where more is not better, and food is the safe path.

Next, we reach one of the most talked-about B vitamins of all: B12, essential for nerves and blood, and the one vegetarians and vegans most need to watch.

This article is intended as general nutritional information and is not a substitute for personalized advice from a doctor or registered dietitian.