Best and Worst Countries for Environmental Skin Aging

Did you know that the Google search term ‘Skin Aging’ has been steadily increasing for the past 16 years?

The topic of skin aging remains relevant for diverse reasons, including a global trend of population aging, growing awareness of skin health, research progress on skin aging, and the existence of unrealistic body standards due to the beauty industry's impact. It is also worth noting that skin conditions may impact quality of life and mental health.

Skin aging is a complex process when the signs of aging appear due to various structural and functional changes in the skin. These signs include wrinkling, pigmentation, sagging, thinning, dryness, and more. There are two types of skin aging — intrinsic and extrinsic. Intrinsic aging is caused by natural physiological processes in the skin and occurs over time. In contrast, extrinsic aging is related to environmental and lifestyle factors we can control.

Lifestyle factors include nutrition, tobacco use, stress, sleep, and others, whereas environmental factors cover sun exposure, air pollution, and climate. While lifestyle completely depends on your everyday choices, environmental factors are harder to control since they are determined by the geographic location and the factors that arise from it.

The Healthnews team created an Environmental Skin Aging Index to evaluate the effect of geographic location on skin aging globally.

Methodology

In the report, we analyzed data from 157 countries, covering around 80% of the United Nations’ member states.

We conducted scientific research and selected metrics for the index based on the following criteria:

• We took evidence from the recent relevant peer‐reviewed scientific review articles.
• We examined data only from human skin studies.
• We included only external environmental factors independent of a lifestyle.
• We covered diverse outcomes of skin aging (pigmentation, sagging, wrinkling, thinning, dryness, lentigines, and more).

Using the above criteria, we selected six metrics: overall solar and ultraviolet (UV) radiation level, particulate matter (PM_2.5), ozone (O₃), and nitrous dioxide (NO₂) pollution level, as well as the prevalence of tobacco use.

• Overall solar radiation level, or more specifically global horizontal solar irradiation, represents the full spectrum of solar radiation (UV radiation, visible light, and infrared radiation) reaching a horizontal surface on earth at a specific location. Multiple studies have proven solar exposure is a major factor in extrinsic skin aging. Thus, the metric carries the highest weight of 55% in the Environmental Skin Aging Index score.
• UV radiation level metric indicates UV exposure level. It contributes 5% to the index value to supplement the main solar radiation metric of global horizontal solar irradiation.
• A metric of particulate matter (PM_2.5) pollution level accounts for 18% of the index. PM_2.5 stands for fine (≤2.5 µm) inhalable solid particles or liquid droplets present in the air. PM_2.5 contains various toxic compounds (e.g., construction dust, soot, sulfates, and others).
• Ozone exposure level indicates the degree of ozone (O₃) pollution at a given location. This metric has a 12% influence on the total index.
• Nitrous oxide exposure level refers to the extent of nitrogen dioxide (NO₂) pollution and has a weight of 8% in the total index score.
• Prevalence of tobacco use is an indirect indicator of the second-hand smoke exposure level. Second-hand smoke consists of various toxic chemical compounds as well as particulate matter. This metric has the lowest impact on the index value as it holds a weight of 2%.

Various studies have demonstrated that air pollution causes extrinsic skin aging. Significant associations with skin aging have been found with air pollutants selected for the index — particulate matter, ozone, nitrous oxide, as well as second-hand tobacco smoke exposure.

For complete data, check here.

Healthnews conducted the study using the steps below:

1. Collected the long-term data for each metric
2. Analyzed the data quality and statistical parameters
3. Examined the correlations between selected metrics
4. Conducted the metric data transformations (if needed) and checked the statistical parameters and correlations afterward
5. Standardized all the metric data to 0–100 ranges
6. Assigned weights to the metrics and calculated index scores for each country
7. Evaluated the reliability and stability of the index calculation method

The index value for each country ranges from 0 to 100. A lower index score suggests that a region has a lower negative effect on skin aging from environmental factors than a higher index score.

So, which regions of the world have the smallest negative impact on skin aging from associated environmental factors?

Top 10 countries with the lowest negative environmental impact on skin aging

Countries from Northern Europe with oceanic or humid continental climates dominate the top 10 in the Environmental Skin Aging Index. Notably, solar radiation metrics play a key role in ranking these 10 countries among the best globally.

Here is a striking example: the difference in solar radiation scores between the countries with the lowest and highest index values is more than 1,200 times! In contrast, the same difference for air pollution is only twofold.

#1 Ireland

Ireland is an island in the British Isles located in the North Atlantic Ocean in Northern Europe. Ireland’s Environmental Skin Aging Index score of 15.15 is the lowest among the countries analyzed, putting it at the top of our list.

Ireland ranks the lowest globally in terms of solar radiation metrics score, while its composite air pollution score is 23rd. Nevertheless, the country’s long-term yearly exposure to particulate matter (PM_2.5) is 2.3 times higher than current World Health Organization air quality guidelines since WHO recommends a PM_2.5 level of 5 μg/m3 or less14.

#2 Norway

Norway is also a Northern European country located on the Scandinavian Peninsula. The country has an Environmental Skin Aging Index score of 15.37, which is very close to Ireland’s result.

In terms of solar radiation, Norway ranks 2nd in the world, while it stands 17th globally for a composite air pollution score. It has relatively low PM_2.5 exposure, yet it is still 1.8 times higher than WHO guidelines.

#3 Sweden

The top 3 on the list is Sweden, which borders Norway to the east and north. The country has a mainly humid continental and subarctic climate scoring 16.70 on the Environmental Skin Aging Index.

Sweden also ranks 3rd in the world for solar radiation metrics and 19th for a composite air pollution metric. Like Norway, Sweden has a relatively low PM_2.5 pollution level, placing it in the 6th spot globally.

#4 Estonia

Estonia is situated near the Baltic Sea and has an Environmental Skin Aging Index score of 18.46. The country ranks 3rd worldwide for solar radiation and 30th for composite air pollution score.

The global horizontal solar irradiation metric places Estonia in the top 4 in the world. Interestingly, for ultraviolet radiation levels, the country is 12th globally. This difference could come from certain atmospheric conditions (e.g., the ozone layer’s status), air pollution levels, or other reasons, including cloudiness or seasonal factors.

#5 United Kingdom

As part of the British Isles, the United Kingdom is considered part of Northern Europe, and like Ireland, it has an oceanic climate.

The Environmental Skin Aging Index for the United Kingdom is 20.33, placing it 5th on the list. Solar radiation scores are very low, while overall air pollution ranks the United Kingdom 42nd.

#6 Denmark

This Northern European country borders the North Sea to the west and the Baltic Sea to the east. Denmark is yet another country on the list with an oceanic climate. The country received an Environmental Skin Aging Index score of 20.94. Additionally, the country stands 7th globally for composite solar radiation. However, it ranks 44th for composite air pollution, mainly because of comparatively high levels of ozone and NO₂.

#7 Lithuania

Lithuania is the largest Baltic nation and has a humid continental climate. With an Environmental Skin Aging Index score of 22.54, the country ranks 7th globally. As for solar radiation, Lithuania is 8th in the world, while it ranks 58th globally for a composite air pollution score.

Like Estonia, Lithuania has a notable difference in ranks of global horizontal solar irradiation and ultraviolet radiation metrics. It ranks 8th in the world for global horizontal solar irradiation and 16th for ultraviolet radiation levels.

#8 Latvia

Like Lithuania, Latvia is located near the Baltic Sea in Northern Europe. Latvia ranks 8th on the list with an Environmental Skin Aging Index score of 23.41. The country has the highest composite air pollution score of the top 10 index countries. However, Latvia’s very low solar radiation level helps it secure a spot in the top 10 countries where the environment is healthiest for your skin.

#9 New Zealand

New Zealand is an island in the southwestern part of the Pacific Ocean, located southeast of Australia’s east coast. The Environmental Skin Aging Index score for New Zealand is 24.40, which places the country in the 9th spot worldwide.

This country is the only one on the list that isn’t from Northern Europe. New Zealand has a very low composite air pollution score — 8th globally. Regarding particulate matter, the country holds 2nd place in the world for the lowest PM_2.5 pollution levels.

#10 Netherlands

The Netherlands is situated near the North Sea in Northwestern Europe. The country has an oceanic climate. With an Environmental Skin Aging Index of 25.25, the Netherlands ranks in the top 10 worldwide. The country ranks 9th globally for solar radiation metric and 76th for composite air pollution metric.

And now, are you interested in learning which regions of the world have the biggest negative impact on skin aging?

Top 10 countries with the biggest negative environmental impact on skin aging

Egypt turns out to have the biggest negative impact on skin aging from the environmental factors we analyzed.

Apart from Egypt, Western Asia countries with a desert climate dominate the bottom 10 index rankings. All analyzed Arabian Peninsula countries, including Qatar, Saudi Arabia, Yemen, Oman, Bahrain, and Kuwait, appear in the top 10 countries with the highest index scores globally.

Skin aging topic in the United States

According to Google Trends, skin aging is a relevant topic in the U.S.; for the past five years, the country has ranked first globally for interest in the Google search term ‘Skin Aging.’ In addition, the U.S. held a global anti-aging market share of around 28% in 2023.

Nevertheless, according to our analysis, the U.S. ranks 66th out of 157 countries in the world for the Global Environmental Skin Aging Index. This result is fairly good, and such strong interest in the anti-aging topic might be caused by a combination of various economic, social, and cultural factors.

Notably, the U.S. is the fourth-largest country in the world. Thus, environmental factors, including solar radiation and air pollution, vary quite significantly in different regions of the U.S. The results are quite generalized, as the Global Environmental Skin Aging Index provides an average score for the whole country.