The Best and Worst Cities for Your Skin
Image: Chemberry

Life in the city often offers countless advantages such as convenient public transport, broad shopping options, from small boutiques to large department stores, and access to a wide variety of cultural events. Nevertheless, life in the city also has its disadvantages. At times, it can be stressful and it can entail distress for the skin, the human body’s largest organ, which acts as a barrier from harmful bacteria, helps regulate internal temperature, transforms vitamin D from exposure to sunlight into calcium for healthy bones and is responsible for the sense of touch.

Environmental factors present in cities, such as smog, fine dust, microparticles, UV radiation, humidity and wind speed, as well as lifestyle factors, like stress, have an effect on our skin and can lead to premature ageing, inflammation and diseases, for instance. In order to preserve the skin and select the appropriate range of products to fight urban strain, it is essential to know where these damaging factors have a greater impact. That is why Chemberry, the search engine enabling buyers to find the right chemical ingredients in personal and home care products, aims to raise awareness on which cities are the best and worst for skin health.

We selected 80 cities with the highest populations from all the Organisation for Economic Co-Operation and Development (OECD) nations and from some of the most populous countries in the world. Then, we examined them according to 9 factors that impact skin health, which include the average yearly temperature, number of days of sunlight, average UV radiation index, air pollution, average wind speed, average humidity over a year, the average working hours per person, traffic congestion and average daily cigarette consumption per smoker. The study aims to find out what factors to consider, perhaps more than others, depending on where you live.

The following table reveals in which out of the 80 analysed metropolises, city dwellers must be even more careful to preserve their skin from the urban strain.

SUNAIRSTRESS
#CityCountryOverall score
1Phoenix10.007.084.929.716.8110.007.7310.004.9010.00
2Oslo1.286.459.449.718.723.339.649.178.029.41
3Montreal1.338.757.749.8110.006.398.077.923.509.04
4Munich2.229.577.919.606.865.2810.007.296.949.00
5Vancouver3.228.898.239.988.524.448.075.633.508.41
6Sydney7.677.334.769.765.728.067.876.465.568.10
7Stockholm1.675.429.449.766.433.068.568.134.907.92
9Ljubljana3.895.217.509.199.093.068.308.754.307.91
10Berlin2.836.538.649.433.214.7210.007.086.947.77

## Methodology

Initially, 80 cities with the highest population in the Organisation for Economic Co-Operation and Development (OECD) nations and in some of the most populous countries in the world were selected, excluding those that did not have sufficient data on the factors in this study.

Since the clusters in this study were dissimilar, the scores of all the factors that have an impact on skin health were ranked on a scale between 0 and 10 to facilitate their comparison.

The scores were obtained by applying the following formula:

$Score_{\thinspace i} = \frac{x_i \thinspace - \thinspace x_{min}}{x_{max} \thinspace - \thinspace x_{min}}$

Then, each factor was attributed to one cluster: Sun, Air and Stress.

Each of the clusters was then weighted differently based on the importance of their impact on skin health, with 40% accounting for Sun, 40% for Air and 20% for Stress.