If you are anything like me, your day probably doesn’t get started until you have had your morning cup of coffee. But if you have ever thought about giving up coffee, you might want to think again. Coffee consumption may have effects on Autophagy, a process of cellular component recycling that also occurs during intermittent fasting. Decades of research suggests that potential health benefits of coffee consumption include protection against type 2 diabetes, Parkinson’s disease, cardiovascular disease, liver disease, liver cancer and improved heart health.

Learn more: This Is Your Fasted Body on Coffee (plus Ask Me Anything during a Coffee AMA at LIFEApps this week! I will be responding to your questions LIVE on Facebook Messenger from 10AM – 1PM Central US time on Weds, May 22nd. Click here to pre-register for our Coffee AMA and be notified when it starts!)

Coffee is one of the most widely consumed beverages worldwide. With hundreds of different types of brews, roasts and blends of coffee alone, without considering the variety of different creamers, butters, oils, spices and sweeteners that can complement your preferred cup of coffee, it’s easy to see how any casual consumer or coffee-aficionado could create a beverage unique to their liking.

I will be covering the differences in brewing techniques, coffee additives and popular meal replacement forms of coffee like the popular “bulletproof” coffee in another blog post. For now, the focus will be on the primary health effects that decades of scientific research have shown us on this popular beverage, and how it can be a powerful tool when combined with intermittent fasting.

Begin your autophagy journey with coffee and fasting. Photo by Danielle MacInnes on Unsplash.
Begin your autophagy journey with coffee and fasting. Photo by Danielle MacInnes on Unsplash.

Benefits and Risks of Coffee Consumption

A comprehensive review published in the Annual Review of Nutrition focused on coffee and caffeine consumption with various health outcomes. Meta-analyses of observational and randomized controlled trials suggest many potential health benefits and some risks, but overall a reduced risk of mortality associated with coffee consumption.

Benefits of Coffee Consumption:

Coffee consumption has been associated with the following health outcomes:

  • Protection against various form of cancer including breast, liver, colon, endometrial and prostate cancer
  • Protection against Parkinson’s disease (1,2)
  • Protection against Type 2 diabetes (3)
  • Protection against liver disease (4)
  • Protection against heart disease (5)
  • Improved cognitive function
  • Weight loss
  • Antioxidant effects
  • Improved cardiovascular health (5)
  • Protection against liver cirrhosis
  • Reduced mortality

Risks of Coffee Consumption:

Drinking too much coffee can result in very unpleasant adverse effects, especially related to the caffeine (6) that is found in the coffee.

  • Increased anxiety symptoms (7)
  • Insomnia
  • Irregular heartbeat
  • Reduced sleep cycles

You may be familiar with the various stages of fasting, but let’s review the key points to guide you in understanding how coffee consumption can affect your fast and promote the cellular recycling process of autophagy.

Autophagosomes within a cell, recycling cellular components.
Autophagosomes within a cell, recycling cellular components included misfolded proteins. Credit: PLoS Biol 4(12): e442. doi:10.1371/journal.pbio.0040442.

Autophagy – the cellular recycling mechanism

Autophagy is our cells’ self-digestive mechanism that recycles waste material and old proteins as energy. The autophagy process has been linked to protective benefits against neurodegenerative diseases in the brain like Parkinson’s, Alzheimer’s and dementia. Fasting-induced autophagy has also been shown to dramatically increase the amount autophagosomes (organelles that carry out recycling of cellular components during autophagy) in the liver, heart, muscle and even brain tissue during the fasted state.

Recent research suggests that chronic disruption of the autophagy processes can be linked to numerous negative health outcomes. Researchers are now trying to unlock what can hack this autophagy process for increased longevity.

Fasted State

When you are fast for ~12 hours or more, you enter a metabolic state called ketosis. In this state, your body starts to break down and burn fat. Some of this fat is used by the liver to produce ketone bodies. Ketone bodies, or ketones, serve as an alternative energy source for your brain cells and cells in other tissues when glucose isn’t readily available.

When the body is depleted of glucose or sugar, the insulin signaling pathway and mTOR pathways that are responsible for cellular growth are inhibited or in other words “temporarily turned off.” This inhibition of the “Mammalian target of rapamycin” or mTOR pathway signals to the body that the genes responsible for cellular growth can take a break, while the genes responsible for fat metabolism, stress resistance and damage repair should be turned on through the AMP-activated protein kinase (AMPK) pathway.

Caffeine’s Effect on Autophagy

A study published in the journal Biochemical and Biophysical Research Communication investigated the power of caffeine to induce autophagy in the skeletal muscle of rats. The researchers concluded that caffeine promoted AMPK-dependent autophagy through calcium-mediated pathways in the skeletal muscle.

This does not exactly mean that high levels of caffeine are necessarily required for maximizing the effects of autophagy in our cells. But a little caffeine early in your day may increase that valuable recycling time as you fast.

In a study published in the journal Cell Cycle, researchers looked at the effects of both caffeinated and non-caffeinated coffee on autophagy. They found that both natural and decaffeinated brands of coffee resulted in rapid autophagy in mice 1-4 hours after coffee consumption. The increase in autophagy was observed in all of the investigated organs including the liver, heart and muscle tissues.

The rapid onset of autophagy with consumption (by mice) of both caffeinated and decaffeinated forms of coffee was accompanied by the inhibition of enzymatic activity of mTOR (which fasting also inhibits!). Coffee consumption was also associated with a broad deacetylation of cellular proteins. Protein deacetylation, where molecules called acetyl groups are removed from lysine residues in proteins, is a change that also happens with caloric restriction or fasting in animal models. Deacetylation of key proteins is known to turn on autophagy. It just so happens that antioxidant compounds found even in decaffeinated coffee can also deacetylate key proteins to turn on autophagy.

This research suggests that while caffeine can play its own important role in autophagy, compounds that not removed in the decaffeination process, presumably polyphenols, may have an even stronger effect on autophagy activation.

Coffee contains powerful antioxidant plant compounds. Image credit: Brigitte Tohm.
Coffee contains powerful antioxidant plant compounds. Image credit: Brigitte Tohm.

Powerful Polyphenols behind Coffee

The suspected compounds responsible for activating autophagy in animals fed coffee are known as polyphenols, a group of compounds found abundantly in natural plant food sources. Polyphenols that have antioxidant properties are known as phytochemicals. Many of the phytochemicals found in natural foods, including coffee, are responsible for different flavors that we can taste as well as different effects on some metabolic pathways.

One of the primary polyphenols found in coffee is chlorogenic acid. It can be found in quantities of up to 70-350 mg per cup and has been linked to numerous health benefits such as reduced risk of some forms of cancer including breast cancer (8). Research published in Biochemical Pharmacology demonstrated that chlorogenic acid can activate AMPK pathways, resulting in improved glucose and lipid metabolism and providing anti-diabetic effects.

Overall, intermittent fasting and coffee consumption have both been shown to inhibit cellular growth pathways in the body and induce the onset of autophagy. Whether you want the extra benefits of a caffeinated beverage in the morning or whether you stick to decaffeinated coffee, your polyphenol-packed beverage may be helping you in the long run for a healthier and longer life.

All the studies included in this review regarding coffee consumption investigated the consumption of black coffee without additives and sweeteners. If you are interested in finding out what you can put in your coffee during your fast and what science-based beverages are great for breaking your fast, then keep an eye out for my next coffee and IF fasting blog post here on the LIFE Apps blog Equilibrium. I will look into the fat-packed bulletproof coffee, spices and sweeteners that don’t break the fast as well as some healthy meal replacement coffee recipes for making the most of your feeding window.

References:

  1. Postuma et al. Caffeine for treatment of Parkinson disease. Neurology. 2012, 79 (7).
  2. Ross et al. Association of Coffee and Caffeine Intake With the Risk of Parkinson Disease. JAMA. 2000, 283 (20), 2674-2679.
  3. Bhupathiraju et al. Changes in coffee intake and subsequent risk of type 2 diabetes: three large cohorts of US men and women. Diabetologia. 2014, 57 (7), 1346-1354.
  4. Bravi et al. Coffee Reduces Risk for Hepatocellular Carcinoma: An Updated Meta-analysis. Clinical Gastroenterology and Hepatology. 2013, 11 (11), 1413-1421.
  5. Mostofsky et al. Habitual Coffee Consumption and Risk of Heart Failure. Circulation: Heart Failure. 2012, 5, 401-405.
  6. Snel & Lorist. Effects of caffeine on sleep and cognition. Progress in Brain Research. 2011, 105-117, 190.
  7. Broderick et al. Caffeine and psychiatric symptoms: a review. The Journal of the Oklahoma State Medical Association. 2004, 97 (12), 538-542.
  8. Iwasaki et al. Plasma tea polyphenol levels and subsequent risk of break cancer among Japanese women: a nested case-control study. Breast Cancer Res Treat. 2010, 124, 827-834.