Could we treat Parkinson’s with natural levodopa?
We are often asked if natural forms of levodopa are the answer to side effect free treatment. Here we investigate the science behind treating Parkinson’s naturally.
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Parkinson’s affects around 145,000 people in the UK. In the early stages of the condition many may not need to take medications. But, as the condition progresses, most will turn to medications to help manage its symptoms.
Levodopa is the most commonly prescribed drug for Parkinson’s. It works by replacing the dopamine that the brain is no longer making. It is a chemical building-block that the body converts into dopamine, and the ‘active ingredient’ that is found in conventional Parkinson’s medications.
Levodopa is very effective, particularly in the early stages of the condition. But as Parkinson’s progresses and more brain cells are lost, more drug will need to be taken to get the same effects. And as the dose is increased to manage the symptoms of Parkinson’s the side effects themselves become unmanageable.
Levodopa in medications
The levodopa in our medications is man-made. The resulting chemical is identical to the levodopa our bodies naturally make. And by making the drug in controlled conditions, we know exactly how much levodopa is in our medications. This allows people to manage their symptoms in a consistent way.
But levodopa can also be found in nature. Some animals and plants make the chemical — including a plant called Mucuna pruriens.
Mucuna pruriens
A tropical legume native to Africa and tropical Asia. It has value in agricultural and horticultural use and has a range of medicinal properties. The seeds provide a natural source of levodopa.
Some people experience side effects with conventional Parkinson’s medications, which may lead them to turn to looking into using Mucuna pruriens, as a natural source of levodopa.
The active chemical in Mucuna pruriens is the same that is in prescription Parkinson’s medication, so it would have the same benefits but also the same side effects. In Ayurveda Indian medicine, Mucuna has long been used to treat conditions such as Parkinson’s, and it may still used in some parts of the world where access to conventional medications is limited.
However, unlike with Parkinson’s medications, it’s hard to control the amount of levodopa you receive when you use natural sources of levodopa. We know that the amount of levodopa in this is low — between 0.58 to 6.42% of the dry weight of the seeds — and, because of the natural variability of levodopa content, someone could end up taking far too much or not enough.
But this isn’t the only downside to natural levodopa when compared to conventional medications.
Improving the performance of levodopa
Our bodies contain proteins that break down levodopa. This means, when levodopa enters the blood stream after been absorbed in the small intestine, much of the drug (around 60–80%) is deactivated before it even has the chance to get into the brain.
To counteract this, today’s medications for Parkinson’s combine levodopa with other drugs — such as carbidopa and benserazide— that block this break down, allowing more of the levodopa to get into the brain.
Levodopa was first combined with other drugs in the 1970s, and levodopa-carbidopa medications were made commercially available in 1975. Today’s combination drugs mean lower doses of levodopa can be taken while still getting the same effect in the brain, which means fewer side effects and better symptom control.
But levodopa from Mucuna pruriens isn’t combined with these levodopa enhancing drugs. So if you could take the same dose, less of the levodopa would get into the brain. And taking more to compensate for the break down would likely result in more side effects, such as nausea and constipation.
At the moment, there has been extremely limited research into the effectiveness and safety of Mucuna pruriens for people with Parkinson’s. And on paper, it would seem that natural levodopa is unlikely to be as effective as, or replace, the medications that are already available. But could there be any benefits of natural levodopa?
Natural levodopa vs. conventional medications
Researchers have investigated the effectiveness of Mucuna pruriens compared to conventional levodopa-carbidopa tablets in a small scale, double-blind clinical trial.
8 people with Parkinson’s took part in the study and were tested on three different medications over the course of a week. The medications were designed so the participants would not know which they were taking. This was done by using placebo pills and powder that looked and tasted the same as the active medications. The drugs that were tested were:
- 200 mg levodopa/50 mg carbidopa in a capsule plus placebo powder dissolved in a glass of water
- 15 g of mucuna seed powder (containing 500 mg of levodopa) dissolved in water, and a placebo capsule
- 30 g of mucuna seed powder dissolved in water (containing 1000 mg of levodopa) plus a placebo capsule
As some of the levodopa in the Mucuna powder would be broken down before reaching the brain, the dose of natural powder was higher in comparison to the conventional capsule formulation.
The researchers found that 15g of Mucuna powder was not enough to control symptoms in this group of participants. But 30g of Mucuna was, in some ways, more effective than the conventional levodopa medication — it appeared to act faster and longer. And, while side effects of Parkinson’s medications were still present, the uncontrollable movements called dyskinesia were not worse when people took the powder compared to the capsule.
On first glance this may seem very positive, however, the researchers also give some explanations about why the powder may have been more effective.They suggest that 30g of powder may have produced higher levels of levodopa in the body than the conventional drugs, even after breakdown, which could help it act longer. Simply increasing the dose of the conventional drug would likely do the same.
They also suspect that the powder could have been absorbed in the small intestine quicker than the capsule, allowing it to act faster. Indeed dispersible levodopa-carbidopa drugs, which can be dissolved in water, have been found to act faster than capsules.
So, from the evidence we have from this study, it looks like Munuca pruriens may not be superior to conventional medication after all. But levodopa isn’t the only ingredient in Mucuna seeds, could other ingredients be having an effect?
Protecting brain cells?
Some researchers have been investigating other properties of Munuca pruriens. We know that levodopa does nothing to prevent or slow the loss of brain cells in Parkinson’s — it simply masks the symptoms for a while. But, in some cell and animal models of the condition, Mucuna pruriens appears to protect cells.
Researchers have suggested that Mucuna pruriens may have inflammatory and antioxidant properties. While we don’t fully understand what else is in these seeds, some point towards an ingredient in Mucuna called Coenzyme Q10 as being the source of these potentially protective effects.
Coenzyme Q10 is a supplement that has received a lot of attention in Parkinson’s. Various studies testing it’s beneficial effects have shown that taking this supplement seems to be safe, even at high doses, but there’s still no evidence of any tangible benefit.
A low cost Parkinson’s medication from beetroot
There is a lack of evidence that natural levodopa is superior to the man-made levodopa in conventional medication. But not everyone has access to these medications. Could levodopa from natural sources help?
Researchers at the University of East Anglia, led by Professor Cathie Martin, are attempting to to produce levodopa cheaply within Africa using an existing natural source of the levodopa chemical in beetroot.
Less than 15% of people in Africa diagnosed with Parkinson’s have access to drugs. This is either because they are unavailable or unaffordable. Medicines are expensive because they cost a lot to produce and import from outside of Africa.
Beetroot contains a natural form of the Parkinson’s drug levodopa — but it is usually broken down into pigments. These pigments give the plants their characteristic colours. The deep purple-red colour of beetroot comes from the presence of red pigment, whilst yellow beetroot instead contains yellow pigment.
Two genes control the breakdown of levodopa into red and yellow pigment. But if these genes are turned off the levodopa would no longer be broken down. This would produce a white beetroot with a large amount of levodopa, which could provide a natural source of levodopa that could be used to make an affordable drug for Parkinson’s.
“ Natural sources of levodopa are often used as alternative treatments for Parkinson’s where drugs are not available. These alternative therapies do not provide an accurate dose of levodopa and can also contain high levels of toxic chemicals that could be harmful.
“If this project is successful, the modified beetroot could be a natural source of levodopa. The levodopa would be extracted and used to produce a pharmaceutical drug of the right dosage. This would provide a low cost medicine that could be produced locally and sustainably in Africa, and improve access to Parkinson’s drugs in the developing world.”
— from Professor Martin’s research summary
Should we treat Parkinson’s naturally?
There is a lack of evidence that natural forms of levodopa are better than conventional medications. The drugs that are available combine levodopa with other compounds that make them more effective and reduce the side effects. But in countries where medications are too expensive or unavailable, natural levodopa could be a lifeline.
But we know that the current treatments for Parkinson’s are not good enough. We need better drugs with fewer side effects, and new treatments that slow or stop the progression of the condition. We’re working hard to develop the treatments of the future and, with your help, we will stop Parkinson’s in its tracks.
The information contained in this blog is not meant as health advice, and should not be used to diagnose or treat any medical condition. You should always consult a qualified health professional or specialist before making any changes to your diet, medications or supplement intake.
