Caffeine: How it Drives a Vicious Cycle of Poor Sleep and Forgetfulness

Have you been more forgetful lately? As we age, many of us struggle to remember everyday details. Examples include remembering what we had for lunch yesterday, the name of that famous actor in all those movies, and the name of the new coworker. Sometimes we attribute this faulty memory to not having enough coffee that morning, or there being too many celebrities to keep up with. This can be true. However, frequently experiencing episodes of faulty memory, or the “tip-of-the-tongue effect”, where you strongly feel as if you know the answer but just can’t recall the word, can be a very frustrating experience. Researchers have discovered that poor memory recall and insufficient amounts of sleep could be the reason we experience these inconveniences throughout the day. 

Impact of Caffeine on Sleep

Unless you are experiencing jet lag, daylight saving time, or have a newborn at home, there could be a number of other things disturbing your natural circadian rhythm. For example, excessive amounts of caffeine. It's a vicious cycle. You’re tired from not getting enough quality sleep, so you reach for a stimulating caffeinated beverage of your choosing to boost energy levels, attention, and mood. However, this widely used stimulant may be the very cause of your sleep troubles. Sometimes we don’t realize just how much caffeine we end up consuming, or how late in the day we are consuming it.

The FDA reports that a mere 400 milligrams (mg) a day should be sufficient for the average person to make it through the day. If you are consuming more than that, you may be putting yourself at risk of over stimulation, which may cause: jitters, heart palpitations, increased heart rate and blood pressure, anxiety, upset stomach, nausea, headache, and insomnia or disrupted sleep. 

Check the nutrition facts on beverage labels to estimate your caffeine intake. Dietary scientists have determined that one of the following 12 fluid ounce (fl oz) drinks contains, on average, the following amounts of caffeine: coffee = 113 - 247 mg, energy drink = 41 - 246 mg, caffeinated soft drink 23 - 83 mg, black tea = 71 mg, and green tea = 37 mg. It is also important to note that decaffeinated coffee is not the same as caffeine free, and some foods such as chocolate may contain about 10 mg of caffeine per 50g bar.

With these numbers in mind, it is not only important to consider how many caffeinated drinks and what kind you are consuming, but when you stop consuming them. Caffeine stays in the bloodstream between 6-10 hours, considering it has about a 4 hour half life. This means that if you last drank a coffee with lunch at 12:00 pm, the last traces of caffeine will not clear your body until about 10:00 pm; and if your last beverage was around 3:00 or 4:00 pm, the caffeine will not leave your system until around 1:00 or 2:00 am, causing you to have difficulties falling asleep well into the early morning.

Health Risks of Excessive Caffeine

The vicious cycle of poor sleep and caffeine intake may also lead to a new problem: taking melatonin. Many individuals resort to taking an over-the-counter melatonin supplement or sleeping pill 30 minutes before bed to help them doze off. However, what many people may not know is that sleeping pills are categorized as sedatives in the medical industry. While melatonin is a naturally occurring hormone that is produced in our brains in response to darkness, artificially supplementing it is doing more harm than good.

To reiterate, taking sleep aids does not result in natural sleep. You are merely sedating the cortical regions of your brain and reducing the amount of deep-sleep activity your brain would encounter during natural sleep. In addition to a poorer quality of sleep, you are likely to experience side effects such as grogginess and forgetfulness the next day, and can experience instances of unconscious actions such as sleep walking, as well as slower reaction times when awake that may lead to vehicular accidents. Even worse is that if you stop taking sleep aids, you can induce rebound insomnia that may be worse than when you initially started the treatment.

Importantly, researchers have found there is no significant difference between the quality of sleep or time taken to fall asleep when comparing 65 separate sleeping drugs to placebo. Therefore, the best thing you can do for yourself is to do everything you can to promote natural, healthy sleep.

Alternative to Caffeine for Energy

  I know that in this day and age, it is much easier to grab a soda or a coffee in the late afternoon to combat 3:00 pm drowsiness or take some melatonin to “fall asleep”. Breaking bad habits can be challenging. However, if you are determined to get consistent, healthy, natural sleep to feel better and rest your body, correcting these behaviors and focusing on your body’s natural processes is an endeavor worth pursuing.

My advice to help with daytime sleepiness is to exercise. Getting sleepy while sitting at your desk? Go for a quick walk, preferably outside or near windows if possible to expose yourself to natural light. You can also stretch, do some light aerobics such as jumping-jacks, or even talk to a friend or coworker for a few minutes to re-energize. If you have time in the morning, evening, or even over lunch, it is also helpful to engage in some form of exercise such as going to the gym, doing yoga, or walking around the neighborhood.

Be sure to also allow yourself enough time to fall asleep (around 30 minutes) and get a full 8 hours of sleep before you need to start the day. You’ll thank yourself later.

References  

Arbon, E. L., et al. “Randomised Clinical Trial of the Effects of Prolonged-Release Melatonin, Temazepam and Zolpidem on Slow-Wave Activity during Sleep in Healthy People.” Journal of Psychopharmacology (Oxford, England), U.S. National Library of Medicine, 28 Apr. 2015, pubmed.ncbi.nlm.nih.gov/25922426/.

“Caffeine.” Caffeine - Alcohol and Drug Foundation, adf.org.au/drug-facts/caffeine/. Accessed 13 Dec. 2024.

Commissioner, Office of the. “Spilling the Beans: How Much Caffeine Is Too Much?” U.S. Food and Drug Administration, FDA, www.fda.gov/consumers/consumer-updates/spilling-beans-how-much-caffeine-too-much. Accessed 13 Dec. 2024.

“Home.” Sleep Foundation, 3 Mar. 2023, www.sleepfoundation.org/.

Huedo-Medina TB;Kirsch I;Middlemass J;Klonizakis M;Siriwardena AN;, T. B., et al. “Effectiveness of Non-Benzodiazepine Hypnotics in Treatment of Adult Insomnia: Meta-Analysis of Data Submitted to the Food and Drug Administration.” BMJ (Clinical Research Ed.), U.S. National Library of Medicine, 17 Dec. 2012, pubmed.ncbi.nlm.nih.gov/23248080/.

“Melatonin: What You Need to Know.” National Center for Complementary and Integrative Health, U.S. Department of Health and Human Services, www.nccih.nih.gov/health/melatonin-what-you-need-to-know. Accessed 13 Dec. 2024.

Mitchell, D. C., et al. “Assessing Dietary Exposure to Caffeine from Beverages in the U.S. Population Using Brand-Specific versus Category-Specific Caffeine Values.” Food and Chemical Toxicology, Pergamon, 25 Mar. 2015, www.sciencedirect.com/science/article/pii/S0278691515001039.

Walker, Matthew P. Why We Sleep: Unlocking the Power of Sleep and Dreams. Scribner, an Imprint of Simon & Schuster, Inc, 2018.