Diet can affect how you well you age, says Henrietta Norton
We start ageing from the day we are born. It is deemed to be a progressive decline in the efficacy of biochemical & physiological processes. To protect our cells from ageing or deterioration we have ‘telomeres’. The longer our telomeres, the greater our protection against cellular ageing. According to the Hayflick theory, our cells can only divide 40-60 times before they reach the ‘Hayflick limit’. With each replication these telomeres shorten, begin to ‘age’ and then die.
The speed at which we reach the Hayflick limit is greatly influenced by one biochemical process known as oxidative stress, which is a by-product of energy production in the mitochondria of every single cell in our bodies. This oxidative stress damages proteins, shorten telomeres and inhibits DNA repair. Oxidative stress accumulates over the life cycle and is associated with degenerative diseases cardiovascular disease, cancer and neurodegenerative diseases.
What about diet?
Oxidative stress can be greatly influenced by what, how and when we eat. This is known as nutrigenomics, the effect of food on gene expression. Certain compounds found in a wholesome diet may help reduce disease risk by influencing specific genes and ‘neutralising’ the impact of oxidative stress. These include natural antioxidants such as EGCG found in green tea, polyphenols in cacao, carotenoids in coloured vegetables such as peppers and sweet potatoes and sulphur-containing foods like onions, leeks and garlic. Herbs and spices, including turmeric, parsley, sage and rosemary, are all naturally rich in antioxidants, too.
Certain foods can also increase this process. Sugar forms advanced glycation end products (AGEs) when it reacts with proteins and fats. This occurs in cooking but also through internal metabolic functions. AGEs are found in colours and flavourings of food such as coatings used on coffee beans and charred meat. Cooking at lower temperatures and minimising sugar intake can help with this process.
Industrial fats and oils are high in oxidative stress products called free radicals. Cook with fats that have a higher ‘burning’ temperature than olive oil. Butter, coconut oil and rapeseed oil are all options to use. Using healthier fats and reducing these industrial oils have also been shown to support brain receptors for dopamine and serotonin that can decline with age.
Gut health
Research has shown a link between the health of the gut and, more specifically, the balance between favourable and less favourable bacteria. In particular, the bifidobacterium species is of the greatest importance in ageing from the gut. It has an immunomodulatory function and reduced levels can increase systemic inflammation. This is the effect also known as ‘inflamm-ageing’. It also affects innate and adaptive immune responses increasing susceptibility to auto-immune diseases and infections. Studies on centenarians indicate that there is greater diversity and bifidobacterium and epidemiological evidence shows that the longest living populations often have a diet rich in fermented, lactic acid-producing products.
Time it right
But how and when we eat is just as important to how quickly our ‘telomeres’ age or shorten. Intermittent fasting (defined as 40 percent less calories than ‘normal’) has shown to be significantly beneficial to slowing the ageing process. Human studies are still preliminary but a two-year CELERIE study (Comprehensive Assessment of Long Term Effects of Reducing Intake of Energy) showed improvements from reducing calorie intake by 25 percent.
Stress less
Practising relaxation methods for just 10-20 minutes a day has been shown to activate genes that prevent cell ageing and control blood sugar and deactivate those responsible for chronic inflammation. Having a good laugh is good for you too, by activating protective genes involved in repair and immune activity.
Sleep more
Adequate sleep is crucial on a molecular level. Sleep deprivation can affect the expression of more than 700 genes, activating those involved in inflammation, immunity and protein damage and turning off those responsible for tissue regeneration. These changes occurred when people slept for less than six hours a night.
Blood levels of melatonin have been shown to increase with increased consumption of foods rich in melatonin, including cherries, pomegranates, oats, grapes, olive oil, tomatoes.
Your healthy ageing superfoods
• Almonds
• Avocados
• Apples
• Beetroots
• Broccoli
• Eggs
• Fermented foods
• Wild salmon
• Garlic
• Green Tea
• Sweet potatoes
Henrietta Norton is a nutritional therapist, author and co-founder of Wild Nutrition (wildnutrition.com ). She has clinics at Grace Belgravia and SP & Co in London.