Parkinson's Disease - Food for the Brain

Parkinson’s Disease is a progressive neurological disorder that is caused by a degeneration of cells in the part of the brain that produces the neurotransmitter dopamine (chemical messenger). It is characterised by loss of motor control such as slowness of movement, rigidity, tremor and balance problems as well as non-movement type symptoms including constipation, low mood, fatigue, sleep and memory problems.

Conventional treatment can involve medication which is primarily aimed at increasing dopamine activity. As dopamine is made in the body from amino acids which are the building blocks of protein, diet can play a key part in ensuring that the right nutrients are available to support the body’s ability to produce dopamine. Optimising nutritional status and addressing co-morbidities such as constipation, depression, fatigue, and insomnia is also an area that can benefit through diet.

Key dietary factors discussed below include reducing toxic load, reducing homocysteine with folic acid, vitamins B12 and B6, zinc and tri-methyl-glycine (TMG) and increasing Omega 3 fats, Vitamin D and Magnesium.

Read on for more information on Parkinson’s Disease and how it can be influenced by nutrition.

What is Parkinson’s disease?

Parkinson’s Disease is a progressive neurological disorder which affects around 120,000 people in the UK. Progressive (or degenerative) means that it typically worsens over time and neurological means that it affects the nervous system (this system includes the brain, spinal cord, and nerves throughout the body). The main symptoms of Parkinson’s are slowness of movement (bradykinesia), rigidity, tremor and postural instability (balance problems). While Parkinson’s is typically described as a ‘movement disorder’, a person with Parkinson’s may experience a range of other symptoms including constipation, low mood, fatigue, sleep and memory problems. Symptoms of Parkinson’s can be grouped into two major categories – motor symptoms (those that affect movement) and non-motor symptoms (those that don’t).

Parkinson’s typically strikes in middle age, with around 80% of cases presenting between ages of 40 and 70, and progression of symptoms is generally slow and continuous. Younger people who develop Parkinson’s are more likely to have a relative with the illness suggesting a stronger genetic component. Symptoms usually begin gradually and motor symptoms are often preceded by non-motor symptoms such as fatigue, loss of smell, depression, constipation and sweating abnormalities.

If you are concerned that you or a friend or family member has symptoms of Parkinson’s, you or they should see a GP immediately.

What causes Parkinson’s disease?

Parkinson’s is caused by the degeneration of brain cells (neurons) in an area of the brain called the substantia nigra. These neurons are responsible for the production of a particular neurotransmitter (chemical messenger in the brain) called dopamine and it is the lack of this neurotransmitter that is responsible for the main Parkinson’s symptoms. The cause of the disease is not known. However, like most degenerative illnesses, it is likely to be due to a range of factors including interactions between genes and environment. Contributory factors may include environmental toxicity, physical trauma, genetics, drugs, disease (including tumours), nutritional deficiency, mitochondrial insufficiency, enzyme deficiency and unremitting stress.

Conventional Treatment

Conventional treatment may involve medication which is primarily aimed at increasing dopamine activity either by providing the precursor (raw material) in the form of levodopa (L-Dopa), or by stimulating dopamine receptors (essentially mimicking dopamine) through the use of a dopamine agonist drug. Also used are drugs called COMT inhibitors which can help the levodopa to be more effective and MAO-B inhibitors which prevent dopamine from breaking down so the limited supply is longer lasting. Other therapies may include physiotherapy, osteopathy, remedial movement, massage, speech therapy, psychological therapy and in some cases surgery (deep brain stimulation). There is no cure for the condition, but these treatments can relieve symptoms.

Nutrition and Parkinson’s disease; what works

So, what does nutrition have to do with Parkinson’s?

1. The neurotransmitter dopamine is made in the body from amino acids which are the building blocks of protein. Every time we eat a protein rich food (such as meat, fish, eggs, chicken and nuts) we take in protein, which the body breaks down into its component amino acids. Two amino acids (L-phenylalanine and L-tyrosine) are converted in the body into L-Dopa, which is then converted into dopamine in the brain.

2. Nutrient co-factors (vitamins and minerals) are required for each stage of this conversion process, so deficiencies of these may reduce dopamine production.

3. L-dopa medication competes for absorption with dietary amino acids, therefore the timing of taking L-dopa and the eating of protein needs to be managed for optimal absorption and effectiveness of the drug and the reduction of side-effects.


Therefore, the nutritional therapy approach to Parkinson’s includes:

1. Supporting dopamine production by ensuring adequate precursors (amino acids) and co-factors (vitamins and minerals)

2. Considering drug-nutrient interactions (and timing of medication) to enhance effectiveness and reduce side-effects

3. Optimising nutritional status and addressing co-morbidities (symptoms that may not be considered to be due to Parkinson’s but occur alongside it and to which a nutritional factor may be contribution). These co-morbidities include constipation, depression, fatigue, and insomnia.

Key Nutrition Factors

Optimise your diet, reduce your toxic load

While the cause of Parkinson’s is not known, environmental toxins such as pesticides and herbicides are implicated. Researchers have found levels of these chemicals to be higher in the brains of Parkinson’s sufferers and incidence of Parkinson’s is higher in areas with greater use of these chemicals. It makes sense to avoid any environmental toxins that you can. Also, consider your intake of dietary toxins such as alcohol and caffeine – avoiding or reducing these may reduce the load on your body’s detoxification pathways.

Key Action:

Ensure that you take in plenty of antioxidants from organic fresh fruits and vegetables. These nutrients may help to combat inflammation (a feature of Parkinson’s) and support your body’s detoxification pathways too.

Eat at least seven portions of fruits and (non-starchy) vegetables daily – lightly cooked or raw to provide plenty of antioxidants.

It also makes sense to optimise your nutrient intake and ensure that your digestive system is working well so that your absorption of nutrients is maximised. Identify any food intolerances and avoid these foods, or you could avoid some of the key culprits (gluten, dairy, soya, yeast) for a trial period of 2-3 weeks to see if this makes a difference to how you feel. Any significant changes to your diet should not be pursued in the long-term without consulting your GP or a nutritional therapist, to ensure that your diet remains balanced.

Keep your blood sugar levels balanced. Eating sugar and refined carbohydrates will give you peaks and troughs in the amount of glucose in your blood; symptoms that this is going on include fatigue, irritability, dizziness, insomnia, depression, excessive sweating (especially at night), poor concentration and forgetfulness. In addition, excess glucose in the blood contributes to inflammation, which is a feature of Parkinson’s.

Key Action:

Eat a diet that will stabilise your blood sugar (known as the Low GL diet): this means eating low GL carbohydrates, as well as combining your low GL carbohydrates with protein in a ratio of 1:1.

Eat at regular intervals: including snacks that include low GL carbohydrate and protein such as fresh fruit with a handful of nuts, oatcakes with humous or celery and cottage cheese.

Sweet Foods: only eat sweet foods as a very occasional treat and only after a meal or healthy snack


Homocysteine is an amino acid which is toxic if elevated, and some studies have found that it is elevated in people with Parkinson’s. At this stage it isn’t known whether higher levels of homocysteine contribute to the development of Parkinson’s or whether the Parkinson’s (or Parkinson’s medications) contributes to higher levels of homocysteine, or both. Either way, reducing homocysteine to a healthy level is a good idea. The nutrients needed to reduce homocysteine include folic acid, vitamins B12 and B6, zinc and tri-methyl-glycine (TMG). Some of these nutrients are co-factors for dopamine production too.

Key Action:

Check your homocysteine: your homocysteine level is an indicator of your B vitamin needs. You can be tested through your GP or using a home test kit. If your level is above 9mmol/l take a combined ‘homocysteine’ supplement of B2, B6, B12, folic acid, zinc, and TMG, providing at least 400mcg of folic acid, 250mcg of B12 and 20mg of B6. If your homocysteine score is above 15mmol/l double this amount.

Eat B vitamin rich whole foods:  whole grains, beans, nuts, seeds, fruits and vegetables. Folic acid is particularly rich in green vegetables, beans, lentils, nuts and seeds, while B12 is only found in animal foods – meat, fish, eggs and dairy produce. A good starting point is also to supplement a multivitamin providing optimal levels of B vitamins, which means 25mg-50mg of B1, B2, B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine) and at least 100mcg of folic acid and 10mcg of B12 and biotin.

Increase your omega-3 fats

The omega-3’s are anti-inflammatory which may be beneficial as neuro-inflammation is a feature of Parkinson’s. Mood problems are also a common feature and there has been a lot of research into the mood-boosting properties of the omega-3 essential fats. A small placebo-controlled pilot trial reported significantly greater improvement of depression in Parkinson’s patients treated with omega-3 fatty-acid supplementation versus placebo. The richest dietary source is from fish such as salmon, mackerel, herring, sardines, trout, pilchards and anchovies.

Key Action:

Eat fish at least twice a week, seeds on most days and supplementing omega 3 fish oils. Look for a supplement that contains EPA, DHA and GLA.

The best fish for EPA, the type of omega 3 fat that’s been most thoroughly researched are: mackerel (1,400mg per 100g/3oz), herring/kipper (1,000mg), sardines (1,000mg), fresh (not tinned) tuna (900mg), anchovy (900mg), salmon(800mg), trout (500mg). Tuna, being high in mercury is best eaten not more than twice a month.

The best seeds are flax seeds and pumpkin seeds. Flax seeds are so small they are best ground and sprinkled on cereal. Alternatively, use flax seed oil, for example in salad dressings. While technically providing omega 3 only about 5% of the type of omega 3 (alpha linolenic acid) in these seeds is converted in your body into EPA.

Vitamin D

Vitamin D is a hot topic for research since it was discovered that we have receptors for this vitamin in the brain, and that it enhances brain-derived neurotrophic factor (BDNF – think of this as akin to a growth hormone for neurons), and is anti-inflammatory. This nutrient is mainly provided by the action of sunlight on the skin.

In a small pilot study, bright light therapy was found to be superior to placebo (less bright light) in Parkinson’s patients. Since vitamin D deficiency is increasingly likely as we get older (and it has a number of implications for health), it makes sense to ensure you have a good level.

Key Action:

Get your vitamin D levels tested: ask your GP or nutritional therapist for a vitamin D test. If your level is below 75 nmol/litre, supplement 2,000 iu per day for 12 weeks, and then get a retest.

Get sensible sunshine exposure: Get some sensible sun exposure, without sun-block, but don’t risk your skin health by allowing yourself to get sunburned!

Up your magnesium

Magnesium is a mineral that acts as a natural relaxant. Some indications of deficiency are: muscle tremors or spasm, muscle weakness, insomnia or nervousness, high blood pressure, irregular heartbeat, constipation, hyperactivity, depression. Magnesium’s role in supporting good sleep may also be quite important here, since many people with Parkinson’s experience poor sleep patterns.

Research on any link between magnesium and Parkinson’s is lacking, however, given its role as a relaxant it is certainly worthy of consideration to reduce spasms and anxiety, and improve sleep.

NB. The dietary recommendations below are suitable for most people. The supplement advice should only be followed if you are not taking medication or have sought the advice of an appropriately qualified health professional.

Key Action:

Increase your magnesium intake through increased intake of green leafy vegetables (eg spinach, kale, cabbage, spring greens etc) and pumpkin seeds. You can also supplement 200-400mg of magnesium daily.

Support Digestion

Support a healthy digestive system by relaxing before you eat and chewing your food thoroughly. Probiotic supplements and/or live yogurt support a healthy gut environment and may be recommended, particularly if you have digestive symptoms.

Relaxation techniques may also be supportive to reduce stress – consider Tai-Chi, yoga, meditation, for example.

You may want to consider whether you have any food intolerances which may impact your health. A trial period of exclusion or a food intolerance test may be used. Any major changes to the composition of your diet should be done with appropriate supervision.

Key Actions:

Optimise digestion and absorption of nutrients by relaxing before you eat and chewing food thoroughly. Eat away from distractions such as television, laptops, phones and work.

Consider taking a probiotic with a wide variety of bacteria strains and at least 15 billion CFUs (Colony forming units – indicates number of viable cells).

Eat fermented food such as sauerkraut and biolive plain natural yoghurt.

Identify food intolerances/try an elimination diet: you may suspect some foods which may or may not be one of the usual suspects – are gluten (wheat, rye, barley), wheat, dairy (all types – cow, sheep, goat, milk, cheese, cream etc), soya, yeast and eggs. If this is the case, you could try an exclusion of the food or foods for a brief trial period.

Get a food intolerance test: alternatively, you could undertake an IgG ELISA blood test to determine whether you have raised antibody levels to specific foods in your blood which is a good indication. Either way, don’t make dramatic changes to your diet or cut out whole food groups without professional guidance to ensure your diet remains healthy and balanced – this is especially important for the frail and for children.


Optimise your diet and reduce your toxic load

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Martignoni E et al., (2007) Homocysteine and Parkinson’s disease: a dangerous liaison? J Neurol Sci. 257:31-7.

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da Silva TM et al., (2008) Depression in Parkinson’s disease: a double-blind, randomized, placebo-controlled pilot study of omega-3 fatty-acid supplementation. J Affect Disord. 111:351-9

Vitmain D

Bright light therapy has been reported to be slightly superior to placebo (with less bright light) in a trial

Paus S et al., (2007) Bright light therapy in Parkinson’s disease: a pilot study. Mov Disord. 22:1495-8