Our world today is drastically different from that in which our bodies developed. Many of which appear to be unfavorable to our health.
This section will quickly highlight a few of some of the most established of these unfavorable changes and how they may be indirectly involved in seborrheic dermatitis progression.
One of the most drastic changes in the modern world it the shift to a drastically more sedentary lifestyle . This reduction in physical activity was primarily caused by social and technological changes that favored convenience. However, as things got more convenient individuals got lazier.
Worse of all we often we fail to realize exactly just how much sitting and sedentary activities we do. If we put this behavior into the spotlight we see some drastic implications.
For example, consider that according to recent data, the average US adult spends more then 60% of their waking day in sedentary behaviors. That’s upwards of 9 hours of sitting each day!
Research on the effects of so much sitting is alarming. High amounts of sedentary time have been associated with:
Well it seems that most people inherently understand these risk factors and try to compensate for them by going to the gym or going for a run. What most individuals are not aware of, is that studies have actually shown that sitting during leisure time was associated with increase mortality rates, even when overall physical activity levels were controlled . Meaning that if you sit all day long, going to the gym for 30 minutes at night may not fully make up for it!
Another critical issue in this area, is that overwhelmingly not only our leisure time is becoming more sedentary, but the modern work place requires people to sit more and more as well. This leads to people sitting both for work and for pleasure. The overall consequences of this are surely detrimental to our healthy.
Sitting can also lead to excessive eating
Interestingly, sitting does not require much caloric expenditure, but sedentary activities (such as watching television, cognitive work, video games, etc) appear to encourage overconsumption of food .
Another major lifestyle change that has occurred in our more recent history is a shift towards the consumption of highly processed food items. This trend was caused by our inherent nature to seek convenience and the high profits these sort of food items have for the producers.
At the most basic level, currently available food falls into three main categories :
- Minimally processed foods – primarily whole foods and those that have undergone minimal processing (cleaning, fermenting, refrigeration, precooking, etc)
- Food extracts – food substances which have been extracted from whole foods (sugar, oil, flour, etc)
- Ultra processed foods – foods that are primarily a combination of food extracts (bread, cookies, breakfast cereal, cereal bars, chips, soft drinks, etc)
Most nutrition and dietary advice fails to take these important distinctions into consideration, instead focusing primarily on nutrients and calories. However, research in this area suggests that calories are not created equal.
Irrespective of calories and nutrients, highly processed food items often have quite a negative impact on our health and immune function . And much of this negative impact has has been attributed to the presence of food additives, ability to induce poor eating habits (snacking, eating while doing other activities), lack of complementary nutrients, and typically high glycemic loads .
Considered together, these factors indicate a drastic change from the food that was available to humans throughout history. But sadly, studies examining the potential link between skin disease and processed food are lacking. There are, however, some potential clues which are relevant. Especially, in the case of a the high glycemic load processed foods typically provide.
Diets with low glycemic loads have been shown to :
- Reduce serum testosterone
- Reduce fasting glucose
- Improve insulin metabolism
- Increase concentrations of SHBG (a protein that plays a vital role in hormone transport)
In turn, these hormonal changes have been shown to be a vital component of normal sebum production . Thus, reducing glycemic load may help stabilize sebum production, reduce topical microbial activity and result in an overall beneficial impact on the skin.
The last lifestyle shift that will be discussed is the extreme surge in antibiotic usage. Antibiotics haven’t been around for that long, but the impact they have had is immense. They’ve become a critical part of modern health care systems and they are used to save lives every single day.
It’s clear that antibiotics have had a huge benefit for a large number of individuals. What is less discussed, is the potential dark side to the abundant antibiotic usage. In fact, numerous studies have linked childhood antibiotic usage to an increased risk of developing asthma, allergic disorders, and various other atopic conditions [15, 16].
In addition to this, research in gut microbiota has shown antibiotics may cause a general shift in the microbial community and dis-balance a vital equilibrium [17, 18]. Potentially, it is this shift in the microbiota of the gut or perhaps even the microbiome of the skin itself, which may result in unstable immune function at later time.
Unfortunately, yet again the research in the case of the negative impact of antibiotics is still very preliminary and the full consequences remain unknown (particularly in skin disease). In any case, due to the unknown dangers which liberal antibiotic usage may carry, their usage should definitely be evaluated more heavily.
Lifestyle Factors in Seborrheic Dermatitis
So far, this section mainly presented some of the most apparent lifestyle shifts which likely play a role in changing the stability of our immune systems. What’s missing is any real connection to seborrheic dermatitis progression.
Nonetheless, there are some specific lifestyle factors which have been shown to increase the change of seborrheic dermatitis. These include:
- Depression and psychological disorders 
- Alcoholism [20, 21]
- Restricted sunlight exposure and increased time in-doors 
- Specific health conditions, which include Parkinson’s and HIV/AIDS 
At the same time, these factors commonly create the conditions (poor diet, hygiene, etc.) which can also have a significant contribution to the progression of skin disease . This makes it rather difficult to single out any one specific factor responsible. Perhaps it’s simply the accumulation of poor lifestyle choices/factors that cause a decline in general health and make an individual more susceptible to infection and disease in the first place.
This section discussed the various lifestyle factors which can suppress the immune system and cause progression of chronic disease such as seborrheic dermatitis. Key points include:
- Society spends far too much time engaged in sedentary activities and this can have a negative impact on immune function and has been linked to various issues
- Most people understand that low levels of physical activity are bad for their healthy, but fail to realize how difficult it may be reverse the damage done
- Ultra processed convenience foods can have a negative impact on our health, irrelevant of their caloric and nutritional content
- One of biggest negative effects of processed foods is the exceedingly high glycemic load they provide, which can cause hormonal changes and increased sebum production
- Antibiotic abuse can lead to permanent changes in the microbial communities of the gut and skin causing poorly understood future implications
- A significant number of studies have shown a link between childhood antibiotic usage and an increased risk of asthma, allergic disorders and other atopic conditions
- Psychological disorders, alcohol abuse, restricted sunlight exposure and presence of various health conditions have all been associated with a higher rate of seborrheic dermatitis