Social media is full of claims that everyday habits can harm your skin. It’s also full of recommendations or advertisements for products that can protect you.

Now social media has blue light from our devices in its sights.

So can scrolling on our phones really damage your skin? And will applying creams or lotions help?

Here’s what the evidence says and what we should really be focusing on.

Remind me, what actually is blue light?

Blue light is part of the visible light spectrum. Sunlight is the strongest source. But our electronic devices – such as our phones, laptops and TVs – also emit it, albeit at levels 100-1,000 times lower.

Seeing as we spend so much time using these devices, there has been some concern about the impact of blue light on our health, including on our eyes and sleep.

Now, we’re learning more about the impact of blue light on our skin.

How does blue light affect the skin?

The evidence for blue light’s impact on skin is still emerging. But there are some interesting findings.

1. Blue light can increase pigmentation

Studies suggest exposure to blue light can stimulate production of melanin, the natural skin pigment that gives skin its colour.

So too much blue light can potentially worsen hyperpigmentation – overproduction of melanin leading to dark spots on the skin – especially in people with darker skin.

2. Blue light can give you wrinkles

Some research suggests blue light might damage collagen, a protein essential for skin structure, potentially accelerating the formation of wrinkles.

A laboratory study suggests this can happen if you hold your device one centimetre from your skin for as little as an hour.

However, for most people, if you hold your device more than 10cm away from your skin, that would reduce your exposure 100-fold. So this is much less likely to be significant.

3. Blue light can disrupt your sleep, affecting your skin

If the skin around your eyes looks dull or puffy, it’s easy to blame this directly on blue light. But as we know blue light affects sleep, what you’re probably seeing are some of the visible signs of sleep deprivation.

We know blue light is particularly good at suppressing production of melatonin. This natural hormone normally signals to our bodies when it’s time for sleep and helps regulate our sleep-wake cycle.

By suppressing melatonin, blue light exposure before bed disrupts this natural process, making it harder to fall asleep and potentially reducing the quality of your sleep.

The stimulating nature of screen content further disrupts sleep. Social media feeds, news articles, video games, or even work emails can keep our brains active and alert, hindering the transition into a sleep state.

Long-term sleep problems can also worsen existing skin conditions, such as acne, eczema and rosacea.

Sleep deprivation can elevate cortisol levels, a stress hormone that breaks down collagen, the protein responsible for skin’s firmness. Lack of sleep can also weaken the skin’s natural barrier, making it more susceptible to environmental damage and dryness.

Can skincare protect me?

The beauty industry has capitalised on concerns about blue light and offers a range of protective products such as mists, serums and lip glosses.

From a practical perspective, probably only those with the more troublesome hyperpigmentation known as melasma need to be concerned about blue light from devices.

This condition requires the skin to be well protected from all visible light at all times. The only products that are totally effective are those that block all light, namely mineral-based suncreens or some cosmetics. If you can’t see the skin through them they are going to be effective.

But there is a lack of rigorous testing for non-opaque products outside laboratories. This makes it difficult to assess if they work and if it’s worth adding them to your skincare routine.

What can I do to minimise blue light then?

Here are some simple steps you can take to minimise your exposure to blue light, especially at night when it can disrupt your sleep:

• use the “night mode” setting on your device or use a blue-light filter app to reduce your exposure to blue light in the evening
• minimise screen time before bed and create a relaxing bedtime routine to avoid the types of sleep disturbances that can affect the health of your skin
• hold your phone or device away from your skin to minimise exposure to blue light
• use sunscreen. Mineral and physical sunscreens containing titanium dioxide and iron oxides offer broad protection, including from blue light.

In a nutshell

Blue light exposure has been linked with some skin concerns, particularly pigmentation for people with darker skin. However, research is ongoing.

While skincare to protect against blue light shows promise, more testing is needed to determine if it works.

For now, prioritise good sun protection with a broad-spectrum sunscreen, which not only protects against UV, but also light.

Michael Freeman, Associate Professor of Dermatology, Bond University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

You’re not in your 20s or 30s anymore and you know regular health checks are important. So you go to your GP. During the appointment they measure your waist. They might also check your weight. Looking concerned, they recommend some lifestyle changes.

GPs and health professionals commonly measure waist circumference as a vital sign for health. This is a better indicator than body mass index (BMI) of the amount of intra-abdominal fat. This is the really risky fat around and within the organs that can drive heart disease and metabolic disorders such as type 2 diabetes.

Men are at greatly increased risk of health issues if their waist circumference is greater than 102 centimetres. Women are considered to be at greater risk with a waist circumference of 88 centimetres or more. More than two-thirds of Australian adults have waist measurements that put them at an increased risk of disease. An even better indicator is waist circumference divided by height or waist-to-height ratio.

But we know people (especially women) have a propensity to gain weight around their middle during midlife, which can be very hard to control. Are they doomed to ill health? It turns out that, although such measurements are important, they are not the whole story when it comes to your risk of disease and death.

How much is too much?

Having a waist circumference to height ratio larger than 0.5 is associated with greater risk of chronic disease as well as premature death and this applies in adults of any age. A healthy waist-to-height ratio is between 0.4 to 0.49. A ratio of 0.6 or more places a person at the highest risk of disease.

Some experts recommend waist circumference be routinely measured in patients during health appointments. This can kick off a discussion about their risk of chronic diseases and how they might address this.

Excessive body fat and the associated health problems manifest more strongly during midlife. A range of social, personal and physiological factors come together to make it more difficult to control waist circumference as we age. Metabolism tends to slow down mainly due to decreasing muscle mass because people do less vigorous physical activity, in particular resistance exercise.

For women, hormone levels begin changing in mid-life and this also stimulates increased fat levels particularly around the abdomen. At the same time, this life phase (often involving job responsibilities, parenting and caring for ageing parents) is when elevated stress can lead to increased cortisol which causes fat gain in the abdominal region.

Midlife can also bring poorer sleep patterns. These contribute to fat gain with disruption to the hormones that control appetite.

Finally, your family history and genetics can make you predisposed to gaining more abdominal fat.

Why the waist?

This intra-abdominal or visceral fat is much more metabolically active (it has a greater impact on body organs and systems) than the fat under the skin (subcutaneous fat).

Visceral fat surrounds and infiltrates major organs such as the liver, pancreas and intestines, releasing a variety of chemicals (hormones, inflammatory signals, and fatty acids). These affect inflammation, lipid metabolism, cholesterol levels and insulin resistance, contributing to the development of chronic illnesses.

The issue is particularly evident during menopause. In addition to the direct effects of hormone changes, declining levels of oestrogen change brain function, mood and motivation. These psychological alterations can result in reduced physical activity and increased eating – often of comfort foods high in sugar and fat.

But these outcomes are not inevitable. Diet, exercise and managing mental health can limit visceral fat gains in mid-life. And importantly, the waist circumference (and ratio to height) is just one measure of human health. There are so many other aspects of body composition, exercise and diet. These can have much larger influence on a person’s health.

Muscle matters

The quantity and quality of skeletal muscle (attached to bones to produce movement) a person has makes a big difference to their heart, lung, metabolic, immune, neurological and mental health as well as their physical function.

On current evidence, it is equally or more important for health and longevity to have higher muscle mass and better cardiorespiratory (aerobic) fitness than waist circumference within the healthy range.

So, if a person does have an excessive waist circumference, but they are also sedentary and have less muscle mass and aerobic fitness, then the recommendation would be to focus on an appropriate exercise program. The fitness deficits should be addressed as priority rather than worry about fat loss.

Conversely, a person with low visceral fat levels is not necessarily fit and healthy and may have quite poor aerobic fitness, muscle mass, and strength. The research evidence is that these vital signs of health – how strong a person is, the quality of their diet and how well their heart, circulation and lungs are working – are more predictive of risk of disease and death than how thin or fat a person is.

For example, a 2017 Dutch study followed overweight and obese people for 15 years and found people who were very physically active had no increased heart disease risk than “normal weight” participants.

Getting moving is important advice

Physical activity has many benefits. Exercise can counter a lot of the negative behavioural and physiological changes that are occurring during midlife including for people going through menopause.

And regular exercise reduces the tendency to use food and drink to help manage what can be a quite difficult time in life.

Measuring your waist circumference and monitoring your weight remains important. If the measures exceed the values listed above, then it is certainly a good idea to make some changes. Exercise is effective for fat loss and in particular decreasing visceral fat with greater effectiveness when combined with dietary restriction of energy intake. Importantly, any fat loss program – whether through drugs, diet or surgery – is also a muscle loss program unless resistance exercise is part of the program. Talking about your overall health with a doctor is a great place to start.

Accredited exercise physiologists and accredited practising dietitians are the most appropriate allied health professionals to assess your physical structure, fitness and diet and work with you to get a plan in place to improve your health, fitness and reduce your current and future health risks.

Rob Newton, Professor of Exercise Medicine, Edith Cowan University

This article is republished from The Conversation under a Creative Commons license. Read the original article.