Are Polyphenols the Next Anti-Ageing Wonder?

What Are Polyphenols?

Have you ever heard of resveratrol? It’s a polyphenol—a natural compound known for its antioxidant and anti-inflammatory properties. It’s increasingly found in skincare products these days.

Resveratrol is also the reason why the belief that a daily glass of red wine is healthy persists—though many experts now see this as a myth. The benefits are largely negated by the harmful effects of alcohol.

But let’s set aside that debate for now. Polyphenols, including resveratrol, are natural compounds found in many plant-based foods, known for their antioxidant and anti-inflammatory properties. They are part of a group of substances called secondary plant metabolites and play a crucial role in protecting the body from free radicals, which are produced through environmental factors or the body's natural metabolism.

Polyphenols vs. Antioxidants: What’s the Difference?

Polyphenols are a subgroup of antioxidants, but not all antioxidants are polyphenols. Antioxidants come in various forms, including vitamins (such as vitamin C and E), minerals (like zinc and selenium), and plant-based compounds—polyphenols being one of them.

That means: Polyphenols are specific antioxidants found in plants, where their primary function is to protect the plant from environmental stressors. Examples of polyphenols include flavonoids, phenolic acids, and lignans, which are found in foods like berries, green tea, and red wine.

Which Foods Are Rich in Polyphenols?

Many plant-based foods are excellent sources of polyphenols. Here are some of the most valuable ones:

• Fruits: Apples, berries, pomegranates, cherries, quinces, citrus fruits
• Vegetables: Artichokes, aubergines, leafy greens, chilli peppers, cabbage, peppers, beetroot, celery, tomatoes, onions
• Nuts: Chestnuts, hazelnuts, almonds, pecans
• Whole grains
• Legumes and soy
• Herbs and spices: Cloves, peppermint, anise, oregano, sage, rosemary, thyme, basil, parsley
• Olives and olive oil
• Cocoa
• Black and green tea
• Coffee

Polyphenols are often responsible for a food’s vibrant colours and distinct flavours. Whether bitter, sharp, or aromatic, foods rich in polyphenols are always a healthy choice.

What Are the Health Benefits of Polyphenols?

Numerous studies highlight the health benefits of a diet rich in polyphenols. Here’s a brief overview of how polyphenols can support your health:

• Heart and circulatory health: Polyphenols help regulate blood pressure and prevent atherosclerosis, reducing the risk of heart disease and heart attacks.
• Metabolic health: They can stabilise blood sugar levels, lowering the risk of type 2 diabetes.
• Brain and nervous system: Polyphenols may protect against neurodegenerative diseases like dementia and Alzheimer’s.
• Cancer protection: Their antioxidant properties can reduce the risk of cancer and may even slow tumour growth.
• Immune system: Polyphenols can ease chronic inflammation and strengthen the immune system against infections.
• Gut health: Polyphenols improve gut flora, benefiting digestion and promoting broader health aspects like immunity and mental well-being.

Additionally, specific polyphenols have targeted health effects. For instance, quercetin, found in cranberries, may help alleviate bladder infections, while capsaicin from chilli peppers can aid in managing migraines.

How Do Polyphenols Work in the Body?

Polyphenols act as antioxidants, neutralising aggressive chemical compounds known as free radicals. These free radicals can form in the body due to UV exposure, environmental toxins, or even through the body’s normal metabolic processes.

Free radicals are highly reactive and can damage any biomolecule they encounter, including DNA. This damage can impair cellular function and even lead to the development of cancer cells. Polyphenols help by reacting with free radicals themselves, neutralising the threat.

Certain polyphenols have additional effects. For example, capsaicin’s effectiveness against migraines is due to its interaction with specific pain receptors. Epicatechin in green tea activates insulin receptors, while lignans from flaxseeds mimic the effects of natural oestrogen in the body.

Are There Risks or Side Effects of Taking Polyphenols?

Polyphenols can sometimes have negative effects. Tannins, which are found in foods like tea, cocoa, stone fruits, berries, and legumes, can inhibit the absorption of copper, zinc, and especially iron from the gut.

This only becomes a concern when tannins are consumed in large quantities, something that’s unlikely with a typical diet. However, those who drink large amounts of tea and suffer from iron deficiency may want to limit tea consumption and avoid drinking it with meals.

When it comes to polyphenol supplements, caution is advised. Overdosing can lead to issues like liver damage. There are no official guidelines for polyphenol intake yet, but studies suggest that a typical diet provides around 900 mg per day, with some variation depending on the country and culture.

What Are the Different Types of Polyphenols?

Polyphenols are a diverse group of over 8,000 compounds. They fall into four main categories, each with distinct chemical structures:

• Flavonoids: The most important group for diet, found in fruits, vegetables, soy, black and green tea.
• Phenolic acids: Present in fruits, vegetables, spices, and tea.
• Stilbenes: Found in grapes, berries, and nuts – resveratrol is part of this group.
• Lignans: Primarily in flaxseeds, sesame seeds, pumpkin seeds, sunflower seeds, and whole grains.

How Can Polyphenols Slow Down Ageing?

Every day, small amounts of damage occur in our bodies, often due to free radicals or chronic inflammation. While these individual damages may seem minor, over time, they accumulate and become noticeable as the signs of ageing.

Polyphenols can’t stop ageing entirely, but their antioxidant and anti-inflammatory properties help slow the process. By reducing oxidative stress and inflammation, polyphenols support healthy ageing and promote well-being into older age.