Cancer, stress

Poor Sleep: Ticket to Insulin Resistance & DNA Damage

These intimidating results of deficient shut-eye are observed after ONE BAD NIGHT. This changes the focus on sleep from a benefit to a necessity.

Insulin resistance is the onramp to diabetes and many other chronic diseases, even cancer. DNA damage can manifest in any number of ways, including cancer as well. We all want to avoid that so, let’s unpack these two studies I saw recently.

I have focused much on sleep over the past years as I have read how critical it is for multiple body systems, and of course how you feel. This applies to our kids as well, and they have an uphill battle with school start times being so early in the morning; see this article for information on how we can help them!

Insulin Resistance After One Night

The one-night aspect grabbed my attention. We are used to seeing a broad packaging of manifestations in diabetics to include sleep issues, but the chicken or egg debate can take over rapidly when trying to determine the cause versus effect.

Partial sleep deprivation during only a single night induces insulin resistance in multiple metabolic pathways in healthy subjects.

A single night of partial sleep deprivation induces insulin resistance in multiple metabolic pathways in healthy subjects.
Donga E1, 1

In healthy subjects – this isn’t just a diabetic problem. In the study, they looked at normal sleep and then threw in a 4 hour night. Any number of circumstances can lead to a bad night like this, the key becomes not making them a regular occurrence.


Insulin resistance at night is actually by design. Since we don’t eat at night, and need our blood sugar to reamin normal, glucose is taken out of the blood stream at a decreased rate.

We do know that at night, melatonin level begins to rise to prepare our brain for sleep. Melatonin also seems to slow down our metabolism, and it acts on the pancreas, which produces insulin.

my notes on this book here

When you don’t sleep well, you get less REM in the second half of the night, and that results in higher levels of cortisol and insulin, which stimulate appetite and lead to greater insulin resistance. In plain terms, this means that a bad night of sleep can throw you into a temporary prediabetic state.

The Telomere Effect: A Revolutionary Approach to Living Younger, Healthier, Longer by Dr. Elizabeth Blackburn, Dr. Elissa Epel

How does a lack of sleep hijack the body’s effective control of blood sugar? Was it a blockade of insulin release, removing the essential instruction for cells to absorb glucose? Or had the cells themselves become unresponsive to an otherwise normal and present message of insulin? As we have discovered, both are true, though the most compelling evidence indicates the latter.

Why We Sleep: Unlocking the Power of Sleep and Dreams by Matthew Walker Loc. 2712

By not properly completing our sleep cycle the period of insulin resistance seems to persist, even after one night of sleep.

DNA Breaks

Decreasing our insulin sensitivity is certainly problematic, but DNA damage? That ramped up my attention, and again this was AFTER ONE NIGHT.

DNA repair gene expression decreased and DNA breaks increased after sleep deprivation. Damaged DNA increased after only one night of sleep deprivation.
Although additional research is needed, this DNA damage may help explain the increased risk for cancer and cardiovascular, metabolic, and neurodegenerative diseases associated with sleep deprivation.
“Although this work is very preliminary, it is clear from the results that even a single night of sleep deprivation can trigger events that may contribute to the development of chronic disease,” said senior author Dr. Siu-Wai Choi, of the University of Hong Kong.

The effect of sleep deprivation and disruption on DNA damage and health of doctors
V. Cheung 2


This, like the sleep study, was small. The method to further substantiating is by adding other mechanistic information. Here are a few more exerpts from books I have read:

Telomeres: As the circadian clock is involved in DNA repair, it also has some effect on maintaining healthy telomeres (the ends of chromosomes). In one study, women who worked the night shift for 5 years or more had reduced telomere length and an associated increased risk for breast cancer.

DNA damage response: If DNA is damaged, it has to be repaired, and the circadian clock regulates some of the repair enzymes so that the repair system is on when the cells are likely to get damaged.

Satchin Panda, The Circadian Code: Lose Weight, Supercharge Your Energy, and Transform Your Health from Morning to Midnight, loc. 3438

Don’t be fooled by its size, because the SCN is incredibly important. It’s your body’s central internal clock. It tells you when to feel tired, when to feel alert, and when to get hungry. It also drives the nightly task of cellular housekeeping, when damaged parts are swept away and DNA is repaired.

Poor quality sleep, sleep debt, and sleep disorders are all linked to shorter telomeres.

The Telomere Effect: A Revolutionary Approach to Living Younger, Healthier, Longer by Dr. Elizabeth Blackburn, Dr. Elissa Epel

Rx: Prioritize Sleep – EVERY Night

Prioritizing sleep is an easy prescription to write. The every night piece becomes the challenge as anyone with a job, kids, stress, etc, can get off track once in a while. So, even though we won’t be perfect, and inevitably will deal with a few bad nights, the goal should be to keep these to a bare minimum at all costs. The consequences of consistent sub-5-hour nights strung together regularly can raise your blood sugar and decrease the capacity for DNA to be repaired. Taken further, the likelihood for diabetes, cancer, and heart disease escalate as shortened sleep sessions increase.


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