Over the years, we have explored several times why our obsession with cleanliness only makes us more vulnerable to infectious disease. And today, we're going to learn about new research that indicates it may also make the youngest and most innocent among us more vulnerable to cancer as well. And the problem is only getting worse.
Although, childhood cancers are "statistically" rare--representing between 0.5% and 4.6%--that still works out to 15,700 kids (ages 0-19) who get cancer each year in the US.1 Worldwide, the numbers range from 50-200 million new cases each year for children. Across all ages of children and across all ethnic and socio-economic groups, cancer is the number one cause of death by disease in children. And while it is true that the overall survival rate has climbed from a mere 10 percent just fifty years ago to nearly 83 percent today,2 for many rare cancers, the survival rate is much lower and has changed little over the years.
And that's the good news. Less rosy is the fact that:
And even, though survival rates have climbed, there is a cost to those improved survival rates; 60% of the children who survive cancer suffer effects later in life such as infertility, heart failure, and secondary cancers6
Professor Mel Greaves, who recently won the Royal Society's prestigious Royal Medal, says that acute lymphoblastic leukemia cancer (again, the most common form of the most common cancer in children) is caused by a combination of genetic mutations and a lack of childhood infection. To be sure, some of his claims fall under the "to a hammer, everything looks like a nail" umbrella. But the core claim, as just stated, does not and is worth exploring in more detail.
In his paper, published in Nature Reviews Cancer, he focuses on ALL, proposing a two-step cause for the disease.7
So far, not very controversial, but now comes the interesting part. He then proposes a dual but conflicting role for common infections. Greaves states that exposure to microbes early in life are protective. But that later infections, if there have been no earlier infections to offer protection, trigger the critical secondary mutations that lead to cancer. To be sure, he also acknowledges that the risk is further modified by inherited genetics, chance, and probably diet. The key line in his paper, though, is:
"Childhood ALL [and in effect, all cancers] can be viewed as a paradoxical consequence of progress in modern societies, where behavioral changes have restrained early microbial exposure. This engenders an evolutionary mismatch between historical adaptations of the immune system and contemporary lifestyles. Childhood ALL may be a preventable cancer."
Or to put that in American English: clean modern homes, antiseptic wipes, and the obsessive desire to protect babies against any infections play a key role in the onset of the most common form of childhood cancer. In fact, statistically, according to Greaves, one in 20 children is born with a genetic mutation that puts them potentially at risk. But they will be fine if their immune system is properly ramped up through exposure to bacteria and viruses in their first year of life. But remember, Greaves poses a dual role for infections. And that is that for those children whose immune systems are not fully functioning because they never had an early challenge--necessary for strengthening and training--they are now susceptible to that deadly second genetic mutation that can trigger ALL cancer when they are exposed to even an insignificant infection like a cold or a flu later in their childhood.
In support of his theory, Greaves points out that ALL is increasing globally at the rate of about 1% a year--and that increase is almost exclusively in affluent populations. ALL rates are low or non-existent in the poorest countries where exposure to dirt is the norm while growing up and where families have lots of children and cross-infection is common. For Greaves, the answer is obvious: "Infectious disease tracks with poverty…The problem is not infection. The problem is lack of infection." In other words, the more infectious disease a child is exposed to early in life, the less likely they are to get childhood cancer. As a side note, Greaves points out that similar trends can be seen in children with type 1 diabetes, Hodgkin's lymphoma, multiple sclerosis and allergies.
In conclusion, Greaves paper states that factors that may decrease a baby's risk include:
Professor Greaves theory found support in a study published in April of 2018 in Cancer Medicine.9 In fact, the researchers even cited Greaves in their study summary, stating, "The findings of these large pooled and meta-analyses add additional evidence to the hypothesis that regular contact with animals in early childhood is inversely associated with childhood ALL occurrence which is consistent with Greaves' delayed infection hypothesis." More specifically, they stated that contact with livestock in the first year of life was inversely associated with ALL and that inverse associations were also observed for contact with dogs and cats in the first year of life.
None of this should be a surprise to readers of this newsletter. I've been saying for over a quarter of a century (yes, it really has been that long), that cancer is fundamentally a disease of the immune system that takes root when your exposure to contaminants gets too high, or the strength of your immune system drops too low. The studies we've talked about today, of course, are an example of the latter.
To be clear, your immune system doesn't cause cancer, but it does protect you from it. As I've explained in previous reports, as part of the normal metabolic process, you produce anywhere from a few hundred to as many as 10,000 cancerous cells each and every day of your life. If your immune system is functioning properly, it can recognize each and every one of those aberrant cells and remove them from your body and destroy them. The reason that everybody doesn't get cancer is because their immune systems can do that. That's just what a healthy immune system does.
According to the National Cancer Institute's (NCI)'s description of cancer and immunity, when normal cells turn into cancer cells, some of the antigens on their surface change. These cells, like many body cells, constantly shed bits of protein from their surface into the circulatory system. Often, tumor antigens are among the shed proteins. These shed antigens prompt action from immune defenders, including cytotoxic T cells, natural killer cells, and macrophages. As the NCI theorizes, patrolling cells of the immune system provide continuous body wide surveillance, catching and eliminating cells that undergo malignant transformation. Tumors develop when this immune surveillance breaks down or is overwhelmed. And the problem with tumors is that once they start to develop, they also develop the ability to hide from your immune system.
What we learned today is that exposure to germs during birth and in your very early years is fundamental to training your immune system--to optimizing it. Without that exposure, you're functioning with a diminished immune system. Thus, your chances of having one of those aberrant cells take root and develop into a tumor--or acute lymphoblastic leukemia as seen in the recent studies--notably increase.
But again, this shouldn't be a surprise to any of our regular readers.
We've explored this issue in detail a number of times. Back in 2016, for example, we looked at several studies that confirmed that you need regular exposure to dirt and germs to keep your immune system in top shape. Being obsessed with cleanliness plays havoc with our immune systems in multiple ways:
The bottom line is: being obsessed with cleanliness only makes you more vulnerable to infection--and as we've now learned, most likely to cancer as well…especially childhood cancer. Simple cleanliness with soap and water is more than enough to keep you clean. Avoid using antibacterial soaps, which harm your health and compromise your immune system. And keep that in mind when cleaning and bathing your children. Regular soap and water will do the trick. And don't obsess about a little dirt on their hands. Remember, exposure to a little dirt only makes them stronger.