Neurodegeneration is a slow and progressive loss of neuronal cells in specific regions of the brain. The degeneration of neuronal cells typically occurs among older people, and it is characterised by five common symptoms which are memory loss, anxiety, dysphoric mood, apathy and disinhibition.
Globally, the burden of neurological disorders continues to rise, due to an increased number of older people. For the first time in history there are more elderly people in the world than young children. There are now around 705 million people over the age of 65 on the planet and 605 million children aged 0-4. There are different reasons as to why this is, such as improvements in life expectancy and a decrease in fertility.
It is very positive that people worldwide are living longer. However, increasing age is a major component in the risk of neurodegeneration. Age along with environmental factors contribute to the development of neurodegenerative diseases, which are becoming a burden to the government who faces the cost of the treatment, rehabilitation and medical centres for these diseases.
The most common neurological disorders are Alzheimer’s disease (AD), Parkinson’s disease (PD), Dementia and multiple sclerosis (MS). These conditions are characterised by progressive loss of neurons until death and an abnormal accumulation of proteins called amyloids. The main consequences are memory loss, oxidative stress, neuroinflammation and impaired energy.
To prevent and slow down neurodegeneration, it is imperative to embrace a diet rich in fruit, vegetables and fatty acids from walnuts and fish oils. These nutrients are the main core of the Mediterranean diet which has been shown to be beneficial in the prevention of neurodegeneration.
The Mediterranean diet is a diet rich in fruit, vegetables, oily fish and olive oil. It includes a moderate consumption of red wine and a low consumption of red meat.
Several studies have demonstrated that the Mediterranean diet along with the DASH diet, which is a diet that also includes high quantity of fruit and vegetables.
The DASH diet excludes cured meat, processed foods and foods high in sodium. Both are promising approaches to slow disease progression and improve quality of life of patients. This is attributed to specific components of the diets such as olive oil, nuts, omega-3 fatty acids, carotenoids and vitamin D that improve cognition.
Particularly, plant polyphenols including resveratrol, which is found in blueberries, dark chocolate and grapes, are known to have neuroprotective effects.
A randomised control clinical trial conducted among 60 elderly (aged 45-85) patients showed that 75 mg of resveratrol taken twice daily for 14 weeks improves verbal memory and overall cognitive performance.
Moreover, recent research has also shown that the ketogenic diet, which is a diet high in fats (around 60% fat), low in carbs (around 6% carbs) and a moderate quantity of protein (around 34%) is beneficial for reducing symptoms for AD (Alzheimer’s) and PD (Parkinson), due to its neuroprotective properties.
This is due to ketone bodies having the ability to increase energy production, reduce inflammation and reduce the number of free radicals (ROS). These are substances that cause damage to the DNA, lipids and proteins and play a key role in the neurodegeneration process.
However, application of the ketogenic diet to elderly people needs to be done with caution, as the diet lacks important macronutrients, the carbohydrates, and often causes loss of appetite. The diet can result in reduced portion sizes and, as a consequence, to further reduction in the supply of essential nutrients. Therefore, it could put the elderly at a higher risk of malnutrition. Due to this, elderly people embracing the ketogenic diet are recommended to supplement the nutrients not provided by the diet, and always consult a doctor first.
Finally, there are two main components found in the brain which have been shown to protect against neurodegenerative diseases: zinc and carnosine.
Zinc is a mineral present in the brain that plays essential roles in learning and memory. The disruption of zinc homeostasis causes Alzheimer’s disease and prion diseases. Carnosine is a protein found in the skeletal muscles and in the brain and is a strong antioxidant.
Zinc can be found in fish, meat, seeds and nuts. Carnosine is largely found in red meat and poultry, and it is not found in plant-based sources. As a result, health professionals advise vegans and vegetarians to incorporate a carnosine supplement into their diet in order to prevent premature aging.
What should you include in your diet?
A diet including healthy portions of the below is recommended to slow the progression of neurodegenerative diseases:
These nutrients are found in both the Mediterranean and DASH diets which have been recommended to protect the nervous system.
The ketogenic diet is also a promising strategy to slow neurodegenerative diseases among the elderly. However, there are concerns regarding reduced appetite and malnutrition. Therefore, further research is needed to evaluate the suitability of the ketogenic diet for people with neurodegenerative diseases.