Research Update: COVID-19 on Surfaces

There are hundreds of papers published every day on the COVID-19 virus. The range of topics borders on the incredible, so I decided to provide two updates based on a couple questions that I’ve gotten. The first is a simple one. How long does the virus live on surfaces? When does it become unable to infect us?

Using standardized procedures that exposed the surfaces to identical amounts of viable COVID-19 virus, researchers tested surfaces under a standard temperature of 68 degrees F and 35-40% humidity. They found the virus was detectable up to seven days on nitrile gloves, four days on chemical-resistant gloves, 21 days on plastic face shields and N95/N100 particulate respirators, and 14 days on stainless steel. All very nice, but how about what appears to be argued about most of the time: cotton masks? The viability of the virus on cotton was reduced within four hours of drying and by 24 hours, was not detectable at all. For a full explanation on the facts behind masks, check out the free Health Info on drchet.com: Cloth Masks: What the Research Says.

The researchers want to check out other materials used in personal protection devices, but the masks are most relevant to you and me. If we can’t wash them between uses, which will kill the virus, letting them dry completely overnight renders the virus unable to infect us. They will continue to protect others as long as we wear them. Respect.

What are you prepared to do today?

        Dr. Chet

Reference: https://doi.org/10.1016/j.matt.2020.10.006

COVID on a Plane

We’re never very far from being reminded about the COVID-19 virus; there’s more info every day. This week, I’ll review three recent scientific papers about the virus. Because I’ve recently flown on an airplane, let’s begin there.

We would logically think that when you have upwards of 150 people crammed into a box that the risk of transmission is going to be high if someone is carrying the virus. My observation, at least on the flights that I was on, is that the airlines try to keep people socially distant, at least as much as possible given the limited space.

One of the things that assist in reducing the risk of transmission is the way that air flows through a plane. The air comes in near the top of the cabin and then circulates down and out at the base of the cabin. Half the air comes from outside the plane while the remainder of the air is circulated through HEPA filters, similar to those found in operating rooms. The risk of viral transmission on an airplane is lower than in office buildings, supermarkets, schools, and commuter trains.

Based on current estimates, there have been only 42 cases of traceable COVID-19 infections from flying. Worldwide! While there are no guarantees, as long as we follow the recommendations of wearing a mask, not traveling while we’re sick, and washing our hands frequently, it appears that it’s a safe way to travel if we really need to fly somewhere.

Just a reminder that there’s an Insider conference call this Wednesday night at 9:00 p.m. ET. On this month’s call, I’m going to introduce a new feature that will be coming to the Insiders subscription portal.

What are you prepared to do today?

        Dr. Chet

Reference: JAMA. 2020. doi:10.1001/jama.2020.19108

The Bottom Line on Cats and Dogs and Supplements

One of my all-time favorite movie lines is by Bill Murray’s character in the original Ghostbusters. He goes on a rant about the coming plague of ghosts and says “…dogs and cats living together…” It’s the delivery more than the words, but it still makes me laugh. I often blurt it out when people talk about all the things that could go wrong if X happens.

I decided to search the literature for specific supplements that can benefit cats and dogs, whether they live together or not. There’s no research on multivitamins-multiminerals per se, although there’s some info on the use of vitamins and minerals as additives to food.

Cats and Supplements

There are two primary areas of research on supplements in cats. The first is the amino acid taurine and the other is joint issues. The lack of taurine in a cat’s diet can result in compromised immune systems, eye problems including blindness, deafness, cardiomyopathy and heart failure, and reproductive issues. Researchers have found that taurine supplementation can increase the taurine level in a cat’s cardiac tissue. One more thing: soy interferes with taurine absorption or utilization, so make sure that the food you feed your cat is soy-free.

The other issue is joint problems such as arthritis. In research on cats, the same blends used in humans that consist of glucosamine, chondroitin, Boswellia, and fish oil help alleviate pain as assessed by owner and veterinarian pain evaluations.

Dogs and Supplements

The big issue with dogs is joint problems such as osteoarthritis. Research shows that the same nutrients recommended for cats and humans are appropriate for dogs: glucosamine, chondroitin, Boswellia, and fish oil. When it comes to amino acids, dogs require 10 essential amino acids to be healthy. While they can get that from vegetarian protein, research shows that dogs can smell it when meals don’t contain all the essential amino acids and will avoid them. That’s some sniffer dogs have!

In the category of interesting research, the amino acid l-arginine together with antioxidants has been shown to benefit dogs with memory issues. Also medium-chain triglycerides are being tested in epileptic dogs to see if the supplement can help reduce seizures. Maybe a teaspoon of coconut oil every day can benefit these dogs—there’s no harm in it while waiting for the research to be completed.

The Bottom Line

We love our cats and dogs and want them to being as healthy as they can be. Targeted supplementation for specific issues is certainly warranted, and it’s probably good to use the same recommendations for us humans and for our best friends: eat better, eat less, and move more. You’ll both be healthier for it!

What are you prepared to do today?

        Dr. Chet

References:
1. Vet Med Sci. 2019 Aug;5(3):325-335. doi: 10.1002/vms3.1822.
2. J Nutr. 1995 Nov;125(11):2831-7. doi: 10.1093/jn/125.11.2831.
3. Am J Vet Res. 1992 Feb;53(2):237-41.

Do Cats Need Vitamins?

Absolutely no way I could write about dogs without talking about cats as well, and there’s good reason: my daughter-in-law is an ardent cat advocate. She and our son act as foster parents for kittens from their local animal society until they’re ready for adoption so that when they join a family, they’re accustomed to being around people. When you have grandcats, even only for a few weeks, you want to see how they’re doing and what Matthew and Kerri have named the latest pair. I also want to see that they do well, so the topic was relevant: can cats take vitamins and minerals?

When the National Academy of Sciences put together the report on dogs, they also did the same type of brochure for cats, and again the quantities seem proportional to body weight.

One difference I noticed about cats is that they require the amino acid taurine to be healthy. As a result, while dogs could do well on a vegetarian diet with enough protein, cats require animal protein. You can check out the entire PDF to get additional information.

What are you prepared to do today?

        Dr. Chet

Reference: www.nap.edu/resource/10668/cat_nutrition_final.pdf

Do Dogs Need Vitamins?

I recently got a question from a long-time listener who asked if it was okay to give the dog a partial serving of their multivitamin-multimineral. I didn’t have a clue—I don’t deal with supplements and animals, with the exception of glucosamine and fish oil. Both are good for dogs, but what about the rest of the supplements?

One supplement I know they don’t need is vitamin C, because dogs can make their own vitamin C. In fact, only humans and one variety of bat can’t make their own vitamin C; all other mammals can. While too much C can be hazardous, the amounts found in most multis for humans should be fine for dogs. But what about the rest of the vitamins and the minerals?

Wouldn’t you know that the same organization, the National Academy of Sciences, that establishes the Dietary Reference Intake for humans has done the same for dogs. In examining the list, they’re in proportion for what humans would take, but proportional based on body weight. The document also goes through the entire nutrition lifecycle of a dog. If you have a dog or dogs, just download this PDF.

And before you ask, we’ll talk about cats on Thursday.

What are you prepared to do today?

        Dr. Chet

Reference: www.nap.edu/resource/10668/dog_nutrition_final_fix.pdf

The Skin Microbiome: Skincare and Cosmetics

While the state of the current pandemic has restricted the ability to socialize to any great degree, it may turn out to be beneficial for the skin microbiome. Be honest. If you don’t have to go to work or out into the public, do you still maintain the same personal grooming practices? Do you put on all your makeup? Based on what people say in virtual meetings, the answer is no. Why is that beneficial for the skin microbiome?

The final potential insult to our skin microbiome is from products we willingly use. Most people apply some form of skincare and/or cosmetic products every day, plus deodorant or anti-perspirant, haircare products, moisturizers, and a plethora of make-up products. Here’s the key point: most of these products contain anti-microbials to maintain the safety of the product before use. That means when applied to the skin, they could also impact the microbiome of the skin.

After reading a review article on the state of research on the entire gamut of skincare products, several researchers outlined the type of research that should be done. While encouraging, that means that not much has been done. I couldn’t find any research that directly examined the impact of skin and cosmetic products on the skin microbiome. We just don’t know.

Strategies for Healthy Skin

There are several things we can do to indirectly help our skin.

  • Drink one-half your body weight in ounces of liquid every day.
  • Take 1 to 4 grams of omega-3 fatty acids every day. There are many reasons to take your omegas, but one is to help reduce the production of inflammatory hormones.
  • Take a probiotic with several types of bacteria with a prebiotic every day. They contribute to a healthy immune system and internal microbiome.
  • There are several supplements that may also contribute to the health of the skin including biotin, vitamin C, and collagen. They may not affect the skin’s microbiome, but starting with a healthier surface may be beneficial.
  • Regular exercise increases blood flow to all areas of the body, including the skin. That can deliver nutrients and help remove waste products.

The Bottom Line

Our skin microbiome is part of our first line of defense against microbial invaders. At this point, there’s not enough research to know whether the skincare routines we’ve become accustomed to are beneficial, harmful, or at least neutral. Is that worth stopping all skincare and cosmetic products? Should we stop taking showers? I don’t think we need to do any of those, but if we start paying more attention to the products we use and make better choices in selecting them, that may give us an edge while science catches up with this amazing part of our immune system.

What are you prepared to do today?

        Dr. Chet

Reference: Int J Cosmet Sci. 2020 Apr;42(2):116-126. doi: 10.1111/ics.12594.

The Skin Microbiome: pH

The water we shower and bathe in may impact our skin microbiome, but we don’t generally just rinse off with water. We use soaps and shampoos as well. How could they impact the microbiome of the skin? Let’s take a look.

Normal healthy skin has a pH range of 5.4 to 5.9. At that pH, the body maintains a normal microbiome. Researchers examined the pH of shampoos and soaps in about 100 different products. Most soaps were highly alkaline with a pH that averaged between 9 and 10. Shampoos fared much better with most in the 6 to 7 pH range.

Will the exposure to these products damage the skin microbiome? If it does, will it be temporary? After all, the exposure will be limited depending on the length of the shower or bath. We don’t have all the answers on that. The closest I’ve seen to sequential testing was a multi-country study that found that the skin pH was still elevated six hours after washing with soap. The rise was less than a single point; still, the actual impact on the microbiome wasn’t evaluated. There’s still much we don’t know.

We’re still not done with the skin microbiome so we’ll finish this up on Saturday.

What are you prepared to do today?

        Dr. Chet

References:
1. Int Microbiol. 2019 Mar;22(1):1-6. doi: 10.1007/s10123-018-00049-x.
2. Indian J Dermatol. 2014 Sep-Oct; 59(5): 442–444. doi: 10.4103/0019-5154.139861.
3. International J of cosmetic science. 2006 DOI: 10.1111/j.1467-2494.2006.00344

The Skin Microbiome: Birth and Water

I began last week’s focus on the skin microbiome based on reading an interview with a scientist who hasn’t taken a shower in over five years (Clean by James Hamblin). We’ve established the basics about skin and the microbes that are supposed to reside in the skin microbiome. This week we’ll cover how the skin microbiome is affected by our environment. What are we doing to our skin that may be impacting our health?

It actually can begin at birth. If we are delivered via the birth canal, we are immersed in vaginal microbes that seed our skin with microbes. In the 1970s, C-sections began to rise from 5% to the current rate of 30%. That means close to one-third of newborns don’t get the initial exposure to skin microbes. Does that result in an increase in skin conditions such as dermatitis? Maybe, but there’s no confirming research to date.

Depending on your water supply, the water may be treated with chlorine and fluoride. While they can kill bacteria to make the water safer, those chemicals may also damage the microbes that live on our skin, hence Hamblin’s avoidance of showers. That impacts the skin microbiome and consequently, our immune system.

What else can impact our skin? I’ll cover more on Thursday.

What are you prepared to do today?

        Dr. Chet

Reference: Int Microbiol. 2019 Mar;22(1):1-6. doi: 10.1007/s10123-018-00049-x.

The Skin Microbes: What They Eat

When we talk about the microbiome of the digestive system, it’s well-known what they eat: sugar. That’s also mostly true for the skin’s microbiome, although those microbes eat other substances as well. In today’s Memo, we’ll cover the types of bacteria and where they’re located. Then we’ll look at their diet.

The Microbes of the Skin

It may come as no surprise that the type of bacteria and other microbe depends on the location. That makes sense: what may grow well in moist areas may not grow well in dry areas.

The sebaceous sites on the head and torso are dominated by species of bacteria that like fatty environments. Remember that sebum is primarily a type of fat, so the type of bacteria that will grow in that area has to be able to thrive in that environment. The Propionibacterium species dominates in the oil glands.

The moist and humid sites contain bacteria such as Staphylococcus and Corynebacterium species. They thrive in the bends of the elbow and the feet, as well as other locations.

Bacteria are not the only important microbes in our microbiome; there are plenty of fungi as well, and I know how gross that may seem to some readers, but try to think about how much you like mushrooms. They’re there to do a job: protect us. The genus Malassezia are found at core body and arm sites. The feet are more diverse in fungi species: Malassezia, Aspergillus, Cryptococcus, Rhodotorula, Epicoccum species as well as others. Here’s something that may comfort some of you: bacteria were the most abundant and fungi were the least abundant.

What about viruses? They seem to be specific to the individual without any single virus dominating. Based on the longitudinal studies of the skin microbiome, they remain largely stable for as long as two years, the length of the longest studies. Pretty amazing considering how the seasons change in places like here in Michigan.

What the Skin Microbes Eat

The skin provides a cool and acidic environment for its residents. The primary nutrients are protein and fats. The microbes have adapted to what’s available in the sebaceous glands, the sweat, and the dead skin cells of the stratum corneum.

For example, the anaerobe P. acnes can survive and thrive by using protein enzymes to break down the amino acids found in the dead skin cells of the corneum stratum. Not only that, they have lipases to breakdown the triglycerides in sebum to use fat as a fuel as well as provide the means for the bacteria to adhere to the skin.

The lipids that can be liberated from the oily sebum and the stratum corneum are also used by the fungi for lipids as they cannot manufacture their own lipids. The Staphylococcus spp. have developed several strategies to survive the dry areas of the body. They’re tolerant of the high salt content of the skin and can use the nitrogen group from urea as a nitrogen source. They also produce chemicals that can break down the stratum corneum to extract nutrients from there as well.

As the researchers who wrote the review paper said, “the skin harbors a heterogeneous community of microorganisms that each have distinct adaptations to survive on the skin.”

The Bottom Line

As you can tell from this week’s memos, the skin microbiome is not just a few bacteria that decided to take up residence and are along for the ride; they have adapted to their environment to survive. How are they impacted by the water we bathe in, the soap we use, and the chemicals we use to look and smell better? That’s what I’ll write about next week.

What are you prepared to do today?

        Dr. Chet

Reference: Nature Reviews doi:10.1038/nrmicro.2017.157

The Skin Microbiome: Anatomy

The skin microbiome is amazingly complex. Not only do we have all the beneficial bacteria and other microbes, we also have microbes that can be beneficial or damaging depending on how we treat the skin. Let’s begin with location: where are all these microbes located? For that, we need to understand a little bit about the structure of the skin.

The skin is the largest organ of the body and is constructed of two different layers: the outermost or the epidermis and an inner layer called the dermis. The outermost layer called the stratum corneum is composed of dead cells that are chemically crosslinked with each other and with cells below to provide a true barrier. As they’re sloughed off, they’re replaced.

To say “skin is skin” does this organ a disservice. It varies in different locations in the body and provides amazing microenvironments based on UV light exposure, pH, temperature, moisture, and sebum content. What is sebum? That’s the product of sebaceous or oil-producing glands, primarily located on the face, the chest, and the back. The sebum provides a coating that repels water and provides an antibacterial shield to hair and skin.

There are also areas of the body that are moist such as under the arms, between the toes, and in other more private areas. Those areas contain sweat glands which modify the pH of the skin and make it more acidic. That created an unfavorable environment for the growth of some bacteria and other organisms.

That’s the anatomy of the skin. The next question is what type of bacteria and other microbes are found on the skin and exactly what do they eat? We’ll cover that on Saturday.

What are you prepared to do today?

        Dr. Chet

Reference: Nature Reviews doi:10.1038/nrmicro.2017.157