Are you serotonin deficient? Women are far more likely to be low in serotonin than men, partly due to its relationship with the female hormone oestrogen. But a deficiency may be an underlying cause in anyone who frequently feels sad or depressed, particularly during the winter months. Other symptoms of low serotonin include:
• Finding it hard to relax
• Suicidal thoughts • Anxiety
• Becoming easily irritated
• Low sex drive
• Carbohydrate or alcohol cravings
Serotonin is made from a break-down product of protein called an amino acid, and specifically an amino acid called tryptophan. We know that tryptophan is essential for good mood, thanks to research by Dr Philip Cowen from Oxford University’s psychiatry department. He wondered what would happen if you deprived people of tryptophan, so he gave 15 happy volunteers a nutritionally-balanced drink that excluded it. Within seven hours, ten out of 15 noticed a worsening of their mood and started to show signs of depression.
So, does the reverse also apply – ie if a depressed person takes tryptophan, will their mood improve? After reviewing the available studies, Donald Ecclestone, professor of medicine at Newcastle’s Royal Victoria Infirmary, concluded that supplementing tryptophan leads to an increase in the synthesis of serotonin in the brain, improving mood as effectively as some antidepressant drugs. Fish, turkey, chicken, cheese, beans, tofu, oats and eggs are particularly rich in tryptophan. You can also supplement it in a capsule – or take an alternative amino acid called 5-HTP, which suits some people better. I explore this in more detail, and also suggest appropriate meal combinations and supplement doses, in my book The Feel Good Factor. Noradrenalin – the motivation factor Another neurotransmitter deficiency associated with depression and lack of motivation is adrenalin’s ‘brother’ noradrenalin. Common symptoms of not having enough include:
• Low energy
• Poor stamina
• Lack of motivation
• Poor concentration or memory
• Hypersensitivity to physical or emotional pain
• Stimulant cravings like serotonin, noradrenalin is also made from amino acids – specifically phenylalanine and tyrosine. In one double-blind study, where phenylalanine or an antidepressant were administered to 40 depressed patients for a month, both groups reported the same positive response – less depression, anxiety and sleep disturbance. Studies giving tyrosine have also proved positive. Individual amino acid supplements are much more potent that just eating foods rich in amino acids, partly because the cocktail of amino acids in foods compete for absorption, and partly because of the amount provided.
However, it is always good to make sure your diet provides an optimal amount of tyrosine, or its precursor, phenylalanine. These are found in fish, soya products, poultry, meat, eggs, dairy products, butter beans, almonds, peanuts, sesame seeds, pumpkin seeds, wheatgerm and whole oats. I explore the best way to supplement a range of helpful amino acids in The Feel Good Factor, which explains 10 proven ways to boost your mood. I’ll also be touring the UK and Ireland in March on The Feel Good Factor Tour – click here to find out more or book your ticket.