Blueberries: Nature's Defence against Environmental Skin Damage

Introduction

Blueberries are packed with beneficial plant compounds that can help improve human health in various ways. One significant benefit is their ability to protect the skin from damage caused by environmental stress. These stressors, like pollution or UV radiation, can produce harmful molecules called reactive oxygen species (ROS), which can overwhelm the skin's natural defences and lead to oxidative stress.

This stress can speed up ageing and damage the skin. Research suggests that blueberries, whether applied directly to the skin or eaten as part of a balanced diet, can help counteract these effects and keep the skin healthy.^1,2

Understanding the layers and defences of human skin

Human skin, covering an area of about 2 square metres, has different layers serving various functions. The outermost layer called the epidermis, is divided into five layers based on cells called keratinocytes. The top layer, the stratum corneum, is the main barrier against external stressors like UV radiation and bacteria. Beneath the epidermis lies the dermis. Cells such as fibroblasts, along with blood vessels and nerves, reside in the dermis. Finally, the hypodermis, made of fat tissue, acts as a barrier and stores water. Skin serves many functions, including protection, temperature regulation, and sensation.³

Skin also has defences against damage, including many enzymes, which prevent the harmful accumulation of reactive oxygen species (ROS). These enzymes are more concentrated in the epidermis than the dermis. Additionally, non-enzymatic antioxidants like vitamins C and E, glutathione, uric acid, and ubiquinol protect the skin from oxidative damage.

Understanding environmental stressors on skin health

Environmental stressors like ultraviolet (UV) light, ground-level ozone (O3), and particulate matter (PM) can harm the skin. UV light, coming from the sun, creates reactive oxygen species (ROS) in the skin, leading to damage and ageing. 

Ozone, mainly from pollution, doesn't penetrate deep into the skin but triggers reactions causing damage and reducing antioxidants. Particulate matter, a mix of tiny solid and liquid particles in the air, can enter the skin, causing oxidative stress and skin issues like dermatitis. 

These stressors can damage skin cells, making them produce harmful molecules, leading to more damage and inflammation. It's like a chain reaction harming the skin's natural defences and causing various skin problems.⁴

Unlocking the health secrets of blueberries

Blueberries are like little treasure troves packed with goodies for your health. They're bursting with natural compounds called polyphenols, which do all sorts of good things for your body. These polyphenols, like flavonoids and anthocyanins, act like superheroes, fighting off bad guys like inflammation and harmful bacteria. 

Anthocyanins give the berries their vibrant blue colour and supercharge them with antioxidant powers.⁵ These antioxidants swoop in to save the day by hunting down and neutralising harmful molecules called reactive oxygen species (ROS), which can wreak havoc in your body. When you munch on blueberries regularly, these anthocyanins work their magic by increasing their levels in your bloodstream.

They're also loaded with other good things like flavonols, ellagitannins, proanthocyanidins, and various acids. These compounds go through a transformation in your digestive system, thanks to your gut bacteria. The bacteria break them down into smaller, more potent molecules, which then circulate in your blood and spread their health benefits throughout your body. 

They help protect against health problems like cancer, diabetes, heart disease, and even problems with your brain. 

Blueberries aren't just good for your insides; they're great for your skin too! They're packed with vitamins like A, C and E, which are like a spa treatment for your skin. These vitamins help keep your skin healthy, glowing and looking youthful.^6,7

Harnessing the power of blueberries for skin protection

Imagine if you could armour your skin against the harsh effects of the sun and pollution just by applying a simple blueberry extract. Research has shown that applying natural compounds found in blueberries directly onto your skin can help replenish important nutrients that get zapped away by things like ozone (O3) and ultraviolet (UV) light. 

Compounds like vitamins E and C, which are abundant in blueberries, work wonders in restoring your skin's antioxidant levels, making it more resilient to environmental stressors. But that's not all, blueberries contain a special compound called resveratrol, which has been shown to activate a protein and act like a shield, protecting your skin cells from UV and hydrogen peroxide-induced damage, ultimately preventing cell death.⁸

Studies have also found that applying blueberry extracts directly onto skin models can reduce inflammation caused by ozone and UV exposure.⁹ These extracts help keep the skin's inflammatory pathways in check, promoting healthy cell growth. In more advanced skin models, like reconstructed human epidermis and ex vivo skin explants, pretreating with blueberry extract has shown promising results in fending off damage caused by oxidative stress and inflammation triggered by UV radiation.¹⁰ This means that blueberries aren't just a tasty snack; they're like a natural defence system for your skin.

When your skin faces the assault of UV light, it triggers a flurry of inflammatory responses, leading to the production of harmful markers like 4-HNE and COX-2. Applying blueberry extract before UV exposure helps tone down these inflammatory markers.

Now, let's talk about skin barrier function. UV exposure can strip away vital structural proteins, leaving your skin vulnerable to conditions like atopic dermatitis. The blueberry extract comes to the rescue once again, boosting the levels of these proteins and fortifying your skin's protective barrier. 

In a 12-week study, people assigned female at birth (AFAB) with type II diabetes saw significant improvements in skin texture and moisture after using blueberry extract topically. This underscores the remarkable potential of blueberries in promoting healthy, radiant skin. While still unravelling the exact role of blueberry compounds, especially polyphenols, in skincare, one thing's for sure, blueberries pack a powerful punch when it comes to protecting and nourishing your skin.^1,11

So, the next time you're thinking about skincare, consider adding a touch of blueberry extract to your routine. It could be the secret weapon your skin needs to stay strong and healthy in the face of environmental challenges. 

Blueberries: more than just a tasty treat

Have you ever wondered why blueberries are hailed as superfoods? Well, it turns out they're not just delicious; they're also packed with health-boosting properties.

When it comes to your heart and blood vessels, blueberries are like superheroes. Studies have shown that eating blueberries can improve vascular function, keeping your blood flowing smoothly and reducing inflammation. Researchers found that certain inflammatory markers, like IL-6 and CRP, decreased after people took blueberry supplements.

Blueberries also have a knack for fighting oxidative stress, which is like rust for your body. By gobbling up harmful molecules called free radicals, blueberries help protect your cells from damage. While some studies have shown mixed results on the anti-inflammatory and antioxidant effects of blueberries, there's still a lot to learn. Researchers are eager to explore how blueberries might benefit your skin, especially for conditions like psoriasis and hidradenitis suppurativa.

Interestingly, studies in mice have hinted at the skin-saving powers of blueberries.¹² In one study, mice fed a diet rich in blueberries showed improved skin hydration and barrier function, even after being exposed to UVB light. In another study, people who took a skin nutrition supplement containing blueberry extract saw smoother, more elastic skin after just 12 weeks.¹

It turns out that even though blueberry polyphenols might not stick around in high concentrations after you eat them, they still pack a punch for your skin. Here's how it works: When you munch on blueberries, your body breaks down those polyphenols in your gut and gut bacteria do their part, too. After this process, you're left with a bunch of smaller compounds, called phenolic metabolites, floating around in your bloodstream. 

Studies have shown that even at low concentrations, these metabolites can work wonders for your skin. Take epigallocatechin-3-gallate (EGCG), for example—a compound found in blueberries. Researchers discovered that regular consumption of EGCG strengthened the skin's defences against UV damage in rats.¹

Harnessing the gut-skin connection with blueberries

Did you know that what you eat can impact your skin health? Your gut and skin have a special relationship, and blueberries might just be the key to keeping both happy.

Your skin can influence the bacteria in your gut, and vice versa. For example, when people assigned female at birth (AFAB) were exposed to UVB light, their vitamin D levels dropped, which changed the makeup of their gut bacteria.¹³ 

Studies have found that eating these berries can boost certain types of good bacteria in your gut. One of these helpful bacteria is Akkermansia muciniphila, which is often low in people with skin conditions like psoriasis. When mice were fed wild blueberry extract, their levels of Akkermansia muciniphila increased, suggesting that blueberries might help improve symptoms of psoriasis.^14,15

Blueberries have also been shown to increase the levels of other beneficial bacteria in your gut, like Bifidobacteria. These bacteria are commonly found in probiotics and have been linked to lower levels of inflammation in conditions like psoriasis. When people drank a blueberry drink for six weeks, their gut bacteria changed in a big way. They ended up with more bacteria like Faecalibacterium prausnitzii and Ruminococcus bromii, which produce a substance called butyrate. Butyrate is like a superhero for your gut–it fights inflammation and provides energy for your gut cells. These findings suggest that blueberries might be a powerful tool for improving gut health and, in turn, supporting healthy skin.¹⁴

Summary

There are potential benefits of incorporating blueberries into skincare routines, both topically and through diet, to enhance skin health, and shield it from environmental damage. There is a distinction between intrinsic and extrinsic skin ageing, with intrinsic ageing being a natural process influenced by genetic factors and extrinsic ageing resulting from environmental exposures and lifestyle choices. 

While dietary interventions and topical applications can both influence skin ageing, they operate through different mechanisms due to variations in nutrient absorption between the gastrointestinal tract and the skin. Since the epidermis lacks direct blood supply, relying solely on dietary interventions may not effectively deliver nutrients to the skin. Therefore, combining topical and dietary approaches is essential for optimal nutrient delivery to the skin, ensuring comprehensive protection and support against environmental stressors.