Why have depression and anxiety increased over the past several years?

Depression and anxiety have increased in the last 25 years, especially after 2010. We know this is strongly correlated to the development and almost exclusive use of the smart phone. Adolescent depression and anxiety have increased the most, but it has also increased for most age groups. 
 As for the second question, one can find research to affirm that each of these factors contribute and correlate to the increase of depression and anxiety: social media, lack of exercise, poor diet, lack of faith and less church attendance, and working from home. It is important to note that it is “correlational” and not “causal”. 
Let’s look at each one of these individually. 

1. Social media and all screen time:  

Increased time on social media, video games, YouTube, and pornography definitely contribute to the increase of adolescent depression and anxiety. This behavior is training the brain for receiving a “high reward” for “low effort”. This can make normal activities seem much less pleasurable. Spending time on a device also limits in-person social interaction, and as social beings, when this is limited or eliminated from one’s life, it will effect their mental and emotional health. 
Social media often leads to comparing your worst with other’s best. This is especially detrimental for adolescent girls more than adolescent boys. Social media platforms also allow friends to see live updates of all their friend’s activities often including their real time locations. If a teen sees their friends are all together, and they were not invited, this effects their self-esteem, thus increasing feelings of sadness and loneliness. 
Not only does this behavior effect depression and anxiety, it also has a major impact on the health of marriages. It can also lead to addictions including gaming, pornography, and screen time in general. 
If you are interested in learning more about this topic, I would highly recommend the book 
iGen: Why Today's Super-Connected Kids Are Growing Up Less Rebellious, More Tolerant, Less Happy--and Completely Unprepared for Adulthood--and What That Means for the Rest of Us  Jean M. Twenge PhD  

2. Lack of Exercise and poor diet: 
Both of these factors contribute to the rise in depression and anxiety. Each effects the other to create a vicious loop which looks like the following: 

• Low energy from poor diet → less motivation to exercise
• No exercise → worse mood and stress tolerance
• Stress and low mood → cravings for junk food
• Junk food → more inflammation and gut damage → worsening mood

This loop sustains and amplifies anxiety and depression symptoms, especially in children and adolescents. This feedback loop is also amplified with the above factor of screen time. The more kids, and adults, are on their devices, the less movement they are probably getting, and are more than likely reaching or unhealthy foods, thus increasing the changes of experiencing depression and anxiety. 
There is plenty of research to prove regular exercise and a healthier diet are effective antidotes to depression and anxiety. The real challenge is, taking a pill takes a lot less effort and time than exercising and preparing healthy meals do. People have to be committed to putting in the effort and spending the time to take care of themselves physically. 
The following book is a great book explaining the effects exercise has on the brain and mental health: 
Spark by John J. Ratey

3. Lack of Faith. 

This one is an interesting factor. The research goes both ways. While there is sufficient research that shows lack of faith can be associate with higher levels of depression and anxiety, being a part of particular faith groups can also be associated with increased depression and anxiety. There are multiple factors that need to be considered on both sides and I am sure an entire book could be written on both subjects. 

I would break it down into two categories; faith the verb and faith the noun. Faith the verb, I would believe can help reduce depression and anxiety because it provides a sense of meaning and purpose, coping skills, moral framework, hope, and resilience to the challenges of life. Faith the noun, which constitutes a religious group and community can provide a positive social support. All of these can help with depression and anxiety. 

However, on the other hand, there are ways in which faith can cause or add to one’s depression and anxiety if it induces shame and high levels of guilt. If a specific faith community is rigid, judgmental, and fear based, this clearly will not help depression and anxiety. 

Faith communities that promote the golden rule, “Do unto others as you have them do unto you” will more than likely foster positive mental health. 

4. Working from home

Working from home can increase and decrease depression and anxiety. I would say personality plays a key role in what effect this has on an individual. Those who are more introverted by nature will probably have less anxiety and depression working from home, while those who are more extroverted by nature will see an increase of depression and anxiety. 

In conclusion, each of these issues: screen time, lack of exercise, poor diet, lack of faith, and working from home, each have an influence on depression, anxiety, marriage problems, and addiction. When we put time and effort into our physical, mental, and spiritual health, we will less likely suffer from each of these challenges. 
Here are some recent statistics on depression and anxiety: 
Global Rise in Mental Disorders
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• According to the World Health Organization (WHO), the number of people with depression increased by more than 18% between 2005 and 2015.
• In 2021, the Lancet published findings showing a 25% global increase in anxiety and depression during the first year of the COVID-19 pandemic alone.

United States Data

• CDC data (National Health Interview Survey, 2000s–2020s) shows consistent increases in reported symptoms of anxiety and depression, especially post-2010.
• Adolescent depression in the U.S. rose by over 50% between 2005 and 2017, with suicidal ideation doubling in some age groups (Twenge et al., 2017).
• Young women have shown the sharpest increases in mental health disorders.