Category Archives: Common Myths

All, Common Myths

Can You Catch Up on Sleep on the Weekends?

By Aneisha Gupta

Most of us are guilty of staying up late during the week and trying to “catch up” on sleep over the weekend. It might seem like a reasonable solution, but can you really reverse the effects of sleep debt with just a couple of days of rest? Let’s think twice. The science around sleep recovery might surprise you.

Quality sleep enhances memory, metabolism, immune health, and mental performance (1). But recent studies show that weekend catch-up sleep doesn’t fully undo sleep deprivation during the week (2). A recent study examined adults who restricted their sleep during the workweek and attempted to recover with extended sleep on weekends. Researchers measured metabolic health indicators and compared these individuals to those with consistent sleep schedules. The study found that those with inconsistent sleep had higher risks of obesity and metabolic dysfunction. (3)

Another study of the association between weekend catch-up sleep and depression in US adults found that sleeping in on weekends may offer temporary benefits, like reducing daytime sleepiness, but doesn’t fully restore cognitive or metabolic function (4). Even worse, irregular sleep schedules (a phenomenon known as “social jet lag”) can disrupt your body’s circadian rhythms and lead to cardiometabolic diseases (heart disease, type II diabetes, and more) (5).

Harvard Health Publishing adds that weekend recovery sleep might also mislead you into thinking you’ve “reset,” when in reality, the cumulative effects of weekday sleep loss linger (6). Researchers recommend aiming for consistent nightly sleep instead of relying on weekends to make up for it.

So, can you catch up on sleep on the weekends? Not really. A regular sleep schedule beats weekend recovery snoozing. Next time you’re tempted to binge sleep on a Sunday, remember real recovery requires consistency.

Sources

National Institutes of Health. “Why Is Sleep Important?” https://www.nhlbi.nih.gov/health/sleep/why

PMC. “Sleep Compensation over the Weekend: Potential Risks.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10900010/

Sleep. “Weekend catch-up sleep and long-term health.” https://academic.oup.com/sleep/article/47/11/zsae159/7712720

Scientific Reports. “Insufficient weekday sleep and recovery.” https://www.sciencedirect.com/science/article/abs/pii/S2352721823002267

BMC Public Health. “Social jet lag and health behaviors.” https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-025-21551-8

Harvard Health Publishing. “Why weekend sleep-ins won’t fix sleep deprivation.” https://www.health.harvard.edu/blog/weekend-catch-up-sleep-wont-fix-the-effects-of-sleep-deprivation-on-your-waistline-2019092417861

All, Common Myths

Does shaving make hair grow back thicker and darker?

by Aneisha Gupta

It’s one of the most persistent grooming myths out there: if you shave your hair, it’ll grow back thicker, darker, or faster. This belief has shaped how many people approach hair removal, but is there any science behind it? Let’s think twice before accepting this common claim.

Hair might appear thicker after shaving because the razor slices it at the surface, leaving behind a blunt edge (1). This edge can feel coarse or stubbly as it grows out, creating the illusion of darker or denser hair (2). However, multiple clinical studies have confirmed that shaving doesn’t change the color, thickness, or rate of hair growth (3).

A foundational study from 1928 published in Anatomical Record and reaffirmed in Journal of Investigative Dermatology decades later found no measurable difference in hair regrowth after shaving (4). The Mayo Clinic and Cleveland Clinic agree, what you’re seeing is just the natural texture of regrowing hair, not a biological response to shaving (5, 6).

Experts explain that hair growth is controlled by hormones and genetics, not razors. Shaving simply cuts hair at the skin’s surface, without affecting the follicle beneath (7). The angle and bluntness of the regrowth may make it look darker or thicker, especially on areas with denser hair like the legs or face, but the properties of the hair itself remain unchanged.

So, does shaving make your hair grow back thicker and darker? Nope. It’s a visual trick, not a physical transformation. Next time you hear this myth, think twice, and shave with confidence.

Sources

University of Texas at Austin. “Fake Follicle News.” https://sites.utexas.edu/think-twice/2019/02/19/fake-follicle-news-does-shaved-hair-grow-back-faster/

Mayo Clinic. “Hair removal: Does shaving affect hair growth?” https://www.mayoclinic.org/healthy-lifestyle/adult-health/expert-answers/hair-removal/faq-20058427

PMC. “Hair Follicle Structure and Regrowth.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7984395/

Journal of Investigative Dermatology. “Re-examination of shaving and hair regrowth.” https://pubmed.ncbi.nlm.nih.gov/5459955/

Cleveland Clinic. “Does Shaving Make Hair Thicker?” https://health.clevelandclinic.org/does-shaving-make-hair-thicker

Mayo Clinic. “Hair removal myths.” https://www.mayoclinic.org/healthy-lifestyle/adult-health/expert-answers/hair-removal/faq-20058427

PMC. “Anatomy and physiology of hair.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7984395/

All, Common Myths

Do pets reduce stress?

A quarter of pet owners want to make their pets famous on social media | Fox Business

IMG via Fox Business 

Are dogs really human’s best friend? Scientific research has tested the common belief that dogs and other pets can improve our quality of life. Let’s think twice: can our furry friends reduce stress?  

In one controlled trial of 82 university students (1), half watched videos of dogs, while the other half interacted with a dog directly. While both sets of students experienced decreased stress, the decrease was greater for students who interacted directly with the dogs. While the sample size is relatively small, it is sufficient to detect a large effect.  But the experimental groups were not randomly assigned, so other factors may account for the findings.  

A similar randomized control trial of university students and medical residents found that interacting with a dog reduced anxiety and negative mood more than viewing the dog or no exposure (2).   

A study of 53 adolescents diagnosed with post-traumatic stress disorder assigned 30 participants to a dog-training program and 23 to other training programs such as cooking and hairstyling according to their personal interests, (3). Researchers found that the individuals who worked with dogs experienced a greater alleviation in PTSD symptoms and lower depression severity compared to those not working with dogs. 

A study of military veterans and ex-first responders diagnosed with PTSD found that people with service dogs had significantly fewer PTSD-related symptoms, better sleep quality, and better wellbeing. There may be other factors (scientists call these confounders) associated with having a service or companion dog such as greater social support or agency, so a randomized trial is needed to confirm this finding.   

Many of us feel it’s obvious that dogs relieve stress.  But that’s exactly why good experimental science is needed to be certain.  Otherwise, we’ll just prove our bias.  To date, the evidence available does not adequately account for bias and potential confounders. Randomized trials with blinding of evaluators would help.  But it’s not clear what would constitute an adequate control for a live dog companion.  

 

References:

  1. Thelwell E. L. R. (2019). Paws for Thought: A Controlled Study Investigating the Benefits of Interacting with a House-Trained Dog on University Students Mood and Anxiety. Animals : an open access journal from MDPI, 9(10), 846. https://doi.org/10.3390/ani9100846  
  2. Crossman, M. K., Kazdin, A. E., Matijczak, A., Kitt, E. R., & Santos, L. R. (2020). The Influence of Interactions with Dogs on Affect, Anxiety, and Arousal in Children. Journal of clinical child and adolescent psychology : the official journal for the Society of Clinical Child and Adolescent Psychology, American Psychological Association, Division 53, 49(4), 535–548. https://doi.org/10.1080/15374416.2018.1520119 
  3. Maoz, I., Zubedat, S., Dolev, T., Aga-Mizrachi, S., Bloch, B., Michaeli, Y., Eshed, Y., Grinstein, D., & Avital, A. (2021). Dog training alleviates PTSD symptomatology by emotional and attentional regulation. European journal of psychotraumatology, 12(1), 1995264. https://doi.org/10.1080/20008198.2021.1995264 
  4. van Houtert, E. A. E., Rodenburg, T. B., Vermetten, E., & Endenburg, N. (2022). The Impact of Service Dogs on Military Veterans and (Ex) First Aid Responders With Post-traumatic Stress Disorder. Frontiers in psychiatry, 13, 834291. https://doi.org/10.3389/fpsyt.2022.834291