Deficiency of B vitamins has been proven to lead to depression and irritability, with B3, B6, folate (also known as folic acid) and particularly Vitamin B12. The food/mood link is strongest for vitamin B12 deficiency which at its worst may cause anything from depression, poor memory, panic attacks, fatigue, hallucinations, and even mania and psychosis.

Amongst its many other roles, B12 is required for our body to manufacture neurotransmitters serotonin – that old favourite the ‘feel-good hormone’- and dopamine – which is required for feelings of reward, amongst other things. Without sufficient dopamine you may feel tired, moody and unmotivated.

Some diets, lifestyles, illnesses and medications can increase your risk of B12 deficiency. Who is at risk?

1. Potentially, low meat eaters (less than 3 x a week) appear, in general, to have more mental health problems. Meat is a big source of Vitamin B12; it contains tryptophan which is a precursor to serotonin, (see above) which may explain part of the issue.
2. High alcohol intake: Drinking alcohol regularly for more than two weeks decreases vitamin B12 absorption from the gastrointestinal (GI) tract.
3. People with the following illnesses that may typically compromise the GI tract including: B12 deficiency, diabetes, Lupus, Graves disease, Crohn’s, Colitis and those with Coeliac disease may have lower levels of B12.
4. Medications: PPIs (Proton Pump Inhibitors) are stomach acid reducing treatments for GERD, HPylori, ulcers etc, known by names such as Lansoprazole & Omeprazole. They can reduce stomach acid by up to 99% which interferes with nutrient absorption, including B12. If you’ve been on this medication for a few years – consider requesting a B12 test.

Other symptoms of B12 deficiency

A sore tongue (glossitis) can be a sign that you are deficient, as can mouth ulcers and pins and needles and at its worst, dementia.

Which foods can be good sources of Vitamin B12?

If you’re a carnivore, try eating organ meats occasionally. Like humans – large amounts of B12 are stored in animal livers – but you can also enjoy salmon, sardines, beef and whole eggs as sources. Vegetarians – bear in mind that an egg contains only about a quarter of your daily requirement. The B12 is mainly found in the yolk, so if you’re an egg-white omelette kind of person, you might not be getting enough but you may get some via cow’s milk, kefir (fermented milk) and cheese.

How can vegans get enough B12?

For vegans, getting enough B12 is harder. It can be found in some brands of nutritional yeast, fortified plant milks / plant yoghurts / plant cheeses – though brands differ; check ingredients list. There is also some B12 in seaweed such as Nori, and soybean cake Tempeh arising from their exposure to bacteria – though exact amounts will vary.  Don’t depend on these as sufficient sources however – you will still need to supplement.

For those that are found to be B12 deficient – you can get B12 injections from your Doctor.

B12 – an extra warning to new and expectant mothers

Take extra care if you are vegan and you are pregnant or breastfeeding, as low B12 can cause severe and non-reversible developmental delays in infants.

If you’re new to veganism bear in mind it can take a few years for any excess B12 being stored in your liver – to run out. If you have been a strict vegetarian or vegan for more than a couple of years – request a blood test to check your levels.

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