Welcome to the February newsletter. The goal of this newsletter is to provide information and analysis of timely topics from recent articles published in the medical literature. I hope you find this information useful and helpful in your health journey.
I think it's safe to say that we are talking about our immune systems more than ever and there has been a lot of discussion of ways to boost our immune system during this pandemic. The first study looks at foods in our diet that can reprogram our immune system by driving it toward more inflammation. Read on to discover which foods can send us on the way to increased inflammation and lowered immune system function.
Does our diet really affect our skin? Is there an acne diet? Over the years there has been controversy about this. Did that pizza we ate as teenagers really cause outbreaks of acne? The second study is a systemic review of over 50 studies that does answer the question. If you ever wondered which foods are acne promoting and which can protect you from outbreaks, the answer is here.
With many kids going to virtual "school", we are watching them spend hours in front of a screen every day. Many of the issues resulting from prolonged school shutdowns won't be known for years, but this study has some early results in regard to vision. It appears there is a critical time for development of vision in kids and too much screen time and lack of outdoor activities appear to have a detrimental effect on vision.
Information regarding COVID-19 is constantly changing. Here in Wisconsin, we are at the lowest rate of hospitalizations and ICU use since last summer. Our cases have continued to trend downwards. We now have 3 remarkably effective vaccines available which are all very effective against all of the variants out there. Over half of our over 65-year-old population has been vaccinated and the populations eligible for vaccination are expanding. When you have a chance to get vaccinated, I highly recommend it. Despite the doom and gloom our media and some leaders are projecting, things are looking up and there is light at the end of the tunnel.
If you are feeling sick or concerned about symptoms, please call me first. We can discuss your symptoms and decide the best course of action for you, including testing. I have saliva-based COVID-19 PCR tests available in my office with 24+ hour turnaround. Serum antibody tests can be performed as well with a 24-hour turnaround.
Fructose Drives Inflammation
Diet high in sugar fructose may prevent proper function of the immune system
Fructose is the second most abundant sugar found in humans. High fructose foods include sugary drinks, processed foods, and sweets. Its intake has increased substantially due to elevated sucrose (table sugar) and high fructose corn syrup use in food products. Fructose is associated with the development of type 2 diabetes, obesity, and non-alcoholic liver disease. This study found a mechanism through which fructose consumption reprogrammed immune system cells toward inflammatory pathways and even short-term exposure to fructose promoted inflammation.
- Fructose intake has increased substantially throughout the developed world and is associated with obesity, type 2 diabetes and non-alcoholic fatty liver disease. Currently, our understanding of the metabolic and mechanistic implications for immune cells, such as monocytes and macrophages, exposed to elevated levels of dietary fructose is limited. Here, we show that fructose reprograms cellular metabolic pathways to favour glutaminolysis and oxidative metabolism, which are required to support increased inflammatory cytokine production in both LPS-treated human monocytes and mouse macrophages. A fructose-dependent increase in mTORC1 activity drives translation of pro-inflammatory cytokines in response to LPS. LPS-stimulated monocytes treated with fructose rely heavily on oxidative metabolism and have reduced flexibility in response to both glycolytic and mitochondrial inhibition, suggesting glycolysis and oxidative metabolism are inextricably coupled in these cells. The physiological implications of fructose exposure are demonstrated in a model of LPS-induced systemic inflammation, with mice exposed to fructose having increased levels of circulating IL-1β after LPS challenge. Taken together, our work underpins a pro-inflammatory role for dietary fructose in LPS-stimulated mononuclear phagocytes which occurs at the expense of metabolic flexibility.
Fructose causes the immune system to produce more reactive (inflammatory) molecules and causes generalized immune system inflammation. This chronic inflammation, even if low-level, can lead to damage to our cells leading to organ systems not working as they should, which results in chronic disease. Low level inflammation is often associated with obesity and diabetes and leads to higher rates of cancer, heart disease, and dementia in these groups.
During the current COVID-19 pandemic, we have seen more severe disease and mortality in obese patients. It seems likely that this chronic inflammation accompanied by suppression of the immune system (or shunting of the immune system toward inflammatory pathways) is part of the reason for these findings and in fact may be a crucial piece of the puzzle.
So what should we do? Avoid any sugar-sweetened drink (and diet drinks aren't much better). Avoid processed foods and fast foods which often have a lot of added sugar. Anything we do to reduce our overall body inflammation will be helpful to stave off the metabolic changes that result in a less effective immune system and development of chronic disease. It's never too late to improve our nutrition.
|Can foods cause (or prevent) acne?
Can the foods we eat affect our skin, especially in regards to acne? In this 11+ year systematic review the authors evaluated 42 observational studies and 11 interventional clinical trials and found multiple dietary factors associated with acne. Acne-promoting factors include high glycemic index/glycemic load food, dairy products, fatty food, and chocolate, whereas acne-protective foods included fatty acids, fruits, and vegetables.
- Background: Dietary habits may play a non-negligible role in the development, duration, and severity of acne, as shown in past critical review articles on such association.
- Methods: The aim of this systematic review is to supplement data available on scientific literature spanning the last 10 years by inserting the keywords "acne" or "acne vulgaris" and "diet", "nutrition", "food", "chocolate", "dairy", "whey protein", "fatty acid", or "drink" in the timeframe "January 2009-April 2020" within the PubMed database.
- Results: Fifty-three reviewed articles met eligibility criteria. They included 11 interventional clinical trials (seven randomized controlled trials and four uncontrolled open label studies) and 42 observational studies (17 case-control and 22 cross-sectional studies, and three descriptive studies).
- Conclusions: This review reinforces the notion of a rapidly growing exponential trend of interest in this subject by the scientific community. Acne-promoting factors include high GI/GL food, dairy products, fast food, and chocolate, whereas acne-protective factors include fatty acids, fruit, and vegetable intake. The role played by specific dietary components pertaining to different foods, as done for milk (full-fat/whole, reduced-fat, low-fat/skim milk), dairy products (milk cream, ice cream, yogurt, cheese, etc.), or chocolate (cocoa, dark/milk chocolate), remains an unsolved issue and objective of future research.
Over the years there have been many different opinions about the link between diet and acne. This study is a review of over 50 studies and comes to some conclusions we can use. Our diet can influence hormones that can worsen acne. A high glycemic diet will trigger insulin release, which as we discussed above will trigger inflammation (and weight gain). The sugar in fruit juices, sodas, processed foods, and foods containing white flour all have a similar effect of increasing insulin release. Chocolate seems to be a specific trigger. It isn't just the sugar, it's the chocolate (even dark chocolate). Dairy in higher amounts was shown to be a trigger for some, likely due to hormones. Daily intake of fried, spicy, oily, and fast food and saturated fatty acids and trans fatty acids elicited an acne-promoting effect. Frequent intake of fruit (especially green bananas, watermelon) and vegetables (yellow, green leaf, cruciferous, green peas) showed a protective role for acne, likely due to their anti-inflammatory and antioxidant properties. A Mediterranean diet (rich in fruits and vegetables) is considered by the authors to be a "food model" for acne patients.
Every person will likely have their individual food triggers. For people experiencing acne, try keeping a food diary to track outbreaks and any relationship to specific foods. Here are some general guidelines.
Acne aggravating foods
- Dairy (more than 3 times/week)
- Sugary, processed foods (candy, breads, baked goods) with a high glycemic index
- Food high in saturated fats (fried foods, excessive red meat)
- Chocolate (sorry)
Foods that may be helpful for acne
- Whole vegetables and fruit
- Essential fatty acids found in fish, flax, nuts, and avocados
- Mediterranean diet high in fiber, olive oil, vegetables, whole grains
Screen Time and Myopia
Increased findings of nearsightedness in children during COVID lockdown
The incidence of myopia (nearsightedness) has been increasing around the world. This timely study looks at the increased risk of myopia in children and how this accelerated during the lockdowns of the COVID-19 pandemic. The authors compared data over the past 5 years to this past pandemic year to determine if pandemic control efforts, which involved confinement, homeschooling, and reliance on digital screen time, negatively affected children's refractive status, exacerbating and accelerating myopia progression. Myopia prevalence increased 21.5% at 6 years, 26.2% at 7 years, and 37.2% at 8 years compared with earlier years for 6- to 8-year-olds. The authors propose this refraction decrease, which was measured immediately after home confinement ended in June 2020, reflects the outcome of home confinement. The 9- to 13-year-old participants did not experience an equivalent shift in refraction so it appears younger children may be more sensitive to environmental change than older children. Children younger than 6 years were not included, limiting our understanding of when the proposed sensitive period starts.
- IMPORTANCE: Time spent in outdoor activities has decreased owing to home confinement for the coronavirus disease 2019 (COVID-19) pandemic. Concerns have been raised about whether home confinement may have worsened the burden of myopia owing to substantially decreased time spent outdoors and increased screen time at home.
- OBJECTIVE: To investigate the refractive changes and prevalence of myopia in school-aged children during the COVID-19 home confinement.
- DESIGN, SETTING, AND PARTICIPANTS: A prospective cross-sectional study using school-based photoscreenings in 123,535 children aged 6 to 13 years from 10 elementary schools in Feicheng, China, was conducted. The study was performed during 6 consecutive years (2015-2020). Data were analyzed in July 2020.
- EXPOSURES: Noncycloplegic photorefraction was examined using a photoscreener device.
- MAIN OUTCOMES AND MEASURES: The spherical equivalent refraction was recorded for each child and the prevalence of myopia for each age group during each year was calculated. The mean spherical equivalent refraction and prevalence of myopia were compared between 2020 (after home confinement) and the previous 5 years for each age group.
- RESULTS: Of the 123,535 children included in the study, 64,335 (52.1%) were boys. A total of 194,904 test results (389,808 eyes) were included in the analysis. A substantial myopic shift (approximately -0.3 diopters [D]) was found in the 2020 school-based photoscreenings compared with previous years (2015-2019) for younger children aged 6 (-0.32 D), 7 (-0.28 D), and 8 (-0.29 D) years. The prevalence of myopia in the 2020 photoscreenings was higher than the highest prevalence of myopia within 2015-2019 for children aged 6 (21.5% vs 5.7%), 7 (26.2% vs 16.2%), and 8 (37.2% vs 27.7%) years. The differences in spherical equivalent refraction and the prevalence of myopia between 2020 and previous years were minimal in children aged 9 to 13 years.
- CONCLUSIONS AND RELEVANCE: Home confinement during the COVID-19 pandemic appeared to be associated with a significant myopic shift for children aged 6 to 8 years according to 2020 school-based photoscreenings. However, numerous limitations warrant caution in the interpretation of these associations, including use of noncycloplegic refractions and lack of orthokeratology history or ocular biometry data. Younger children's refractive status may be more sensitive to environmental changes than older ages, given the younger children are in a critical period for the development of myopia.
The lockdowns and homeschooling which have taken place over the past year are unprecedented. Many problems resulting from prolonged school closures are yet to be fully understood but this study has some early data on one issue, myopia or nearsightedness. This study found a significant progression of myopia in 2020, which had been stable over the past 5 years. This worsening was seen with the younger kids in grades 1-2 only doing 1 hour online daily and grades 3-6 doing 2.5 hours daily. It is concerning what the results would be with longer screen time. Kids between the ages of 6-8 years appear to be in a critical developmental stage for their vision. When children in this age group have a lack of outdoor activities and increased screen time (and closer screen time) it has important clinical practice implications; children aged 6 to 8 years may be experiencing a critical period for myopia development and girls are more affected than boys. We don't know the age that this critical time starts but we should be quite wary about screen time and confinement for younger children as well. We should emphasize myopia prevention efforts including more time outdoors (at least 2 hours daily), frequent breaks from screen work in children under age 9, although these measures are good for any of us who look at screens all day.
Progression of Myopia in School-Aged Children After COVID-19 Home Confinement JAMA Ophthalmol 2021 Jan 14;[EPub Ahead of Print], J Wang, Y Li, DC Musch, N Wei, X Qi, G Ding, X Li, J Li, L Song, Y Zhang, Y Ning, X Zeng, N Hua, S Li, X Qian
Thank you for taking the time to read through this newsletter. I hope you have found this information useful as we work together to optimize your health. Feel free to pass this on to anyone you think would benefit from this information.
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As always, if you have questions about anything in this newsletter or have topics you would like me to address, please feel free to contact me by email, phone, or just stop by!
To Your Good Health,
Mark Niedfeldt, M.D.