Friday Tidbits #4: Grey rules, Tart Cherry Juice & Sighing
Welcome to Friday Tidbits. This is a very short email with morsels of information to help you tweak your life and health for optimum longevity and healthy ageing.
Nutrition
When is comes to maintaining your weight, sometimes having “black and white rules” about food are easier than “grey rules.”
This time of the year tasty morsels that tempt us to stray from our best intentions seem to be everywhere. Most people put on around 1-4kg (0.65% of a 70kg) (1) between late November to mid January. It is not the Christmas lunch that is the main culprit, it is the little bit extra, everyday, over 8 weeks. Most research show that this weight is not lost after the festive season (2). If you do not make a significant effort to lose this extra weight, you will start at a higher weight the following year. The cumulative effect of a 1kg weight increase per year ends up 10kg in 10 years!
The moderation intention is what I call a ‘grey rule’ - you can have anything, just a little bit. A ‘black and white rule’ propose to eliminate a certain category or food item. And you can decide what that is. For instance: no fried food or no pastries. Or only have the prawns but not the party pies. You can decide what works for you in the situation that presents itself. At the office party, only have the prawn blinis but not the arancini. Or have two pieces of canapés and then skip desert. The ‘rule’ that works for me, is to only have cake if it is homemade.
A little bit of self-imposed restraint now will save a lot of restriction later.
Sleep
Tart cherry juice improves sleep onset and sleep quality (3).
Tart cherries contain melatonin - about 0.125 ug per 100g cherries (4). Melatonin is released by the pineal gland in the brain and helps us fall asleep. The typical supplemental dose of melatonin recommended for sleep is 0.5 - 5 mg.
The antioxidants in tart cherries also appear to increase the availability of tryptophan (4) by reducing inflammation. Inflammation increase the IDO enzyme that is responsible for degradation of tryptophan. Tryptophan is the precursor molecule to serotonin and melatonin. Lasso et al. showed improved sleep efficiency and longer sleep duration over 2 weeks of consuming 240ml juice twice per day (5).
When it comes to supplements for sleep I prefer a little nudge vs a sledgehammer. Tart cherry extract is the nudge compared to the sledgehammer effect of prescribed medication like temazepam and Stilnox.
In supplements look for Montmorency Cherry or Prunus cerasus L. in the listed ingredients. I like this one by Swanson.
Stress
Acute stress reduce working memory function (6) - your ability to remember the five items that you plan to buy at the grocery store or where you parked your car.
Acute stress lasts only for a short time and most of us bounce right back. Some examples are starting a new job, public speaking, sitting an exam and my recent experience, going through the process of buying a new house.
Working memory is defined as a limited-capacity temporary storage system that is being constantly updated (7). We use is to remember the grocery list and more complex tasks including maths and building puzzles. Working memory is limited in the amount of information (6) it can hold and also for how long it can be stored.
One hypothesis is that under high levels of acute stress, it is almost like that part of your brain is full of unwanted thoughts (8) and there is no space left for normal life stuff. Research show conflicting results when the effect of acute stress is tested under laboratory conditions - some show increased working memory function, others show no or negative effects. The many diverse methods used in studies explain some of the discrepancies. Real life events are also likely to have different effects compared to controlled laboratory settings. Person-inherent factors including sex, genetics and psychological factors influence our ability to deal with different levels of stress.
Breathe
Deliberate sighing can induce a sense of calm in periods of stress.
Sighing is an adaptive mechanism that help us change our psychophysiological state by acting as a resetting mechanism (9). We sigh in many instances including in emotional state of relief, at the end of a laugh, when we finished crying, just before we fall asleep and just before we wake up (10). In practical terms; we regulate our emotional state by sighing. We sigh more in times of stress. Sighs facilitate relief and muscle tension is lowered after sighing (9)
Be mindful that excessive sighing can be maladaptive and detrimental to our wellbeing. Conditions associated with too much sighing include asthma, chronic pain, depression, traumatic brain injury and anxiety (9).
Sigh deliberately but not too frequently :).
Move
Muscle power is more important than strength in preventing falls (11).
Falls are the leading cause of injury and related deaths in older adults. As we age we lose muscle strength and power. More simply stated, we can pick and carry less (strength) and we move slower in deliberate and reflexive ways. The latter refers to jumping and moving your feet fast when you trip. If you can move your feet fast, you will reduce the chance of actually falling. Muscle power is the ability to react fast (explode) - the contraction speed of muscle fibers.
Strength and resistance training help retain muscle strength. Typical exercise include dead lift, squats, lunges and step ups. To maintain explosive power, exercises like jumping, skipping or using pneumatic resistance machines (12).
References
Maher, Carol et al. “Weekly, Seasonal, and Festive Period Weight Gain Among Australian Adults.” JAMA network open vol. 6,7 e2326038. 3 Jul. 2023, doi:10.1001/jamanetworkopen.2023.26038
Abdulan, Irina Mihaela et al. “Winter Holidays and Their Impact on Eating Behavior-A Systematic Review.” Nutrients vol. 15,19 4201. 28 Sep. 2023, doi:10.3390/nu15194201
Howatson, Glyn et al. “Effect of tart cherry juice (Prunus cerasus) on melatonin levels and enhanced sleep quality.” European journal of nutrition vol. 51,8 (2012): 909-16. doi:10.1007/s00394-011-0263-7
Burkhardt, S et al. “Detection and quantification of the antioxidant melatonin in Montmorency and Balaton tart cherries (Prunus cerasus).” Journal of agricultural and food chemistry vol. 49,10 (2001): 4898-902. doi:10.1021/jf010321+
Losso, Jack N et al. “Pilot Study of the Tart Cherry Juice for the Treatment of Insomnia and Investigation of Mechanisms.” American journal of therapeutics vol. 25,2 (2018): e194-e201. doi:10.1097/MJT.0000000000000584
Geißler, C. F., Friehs, M. A., Frings, C., & Domes, G. (2023). Time-dependent effects of acute stress on working memory performance: A systematic review and hypothesis. Psychoneuroendocrinology, 148, 105998. https://doi.org/https://doi.org/10.1016/j.psyneuen.2022.105998
Lukasik, K. M., Waris, O., Soveri, A., Lehtonen, M., & Laine, M. (2019). The Relationship of Anxiety and Stress With Working Memory Performance in a Large Non-depressed Sample [Original Research]. Frontiers in Psychology, 10. https://doi.org/10.3389/fpsyg.2019.00004
Klein, K. and Boals, A. (2001), The relationship of life event stress and working memory capacity. Appl. Cognit. Psychol., 15: 565-579. https://doi.org/10.1002/acp.727
Vlemincx, E., Severs, L., & Ramirez, J.-M. (2022). The psychophysiology of the sigh: II: The sigh from the psychological perspective. Biological Psychology, 173, 108386. https://doi.org/https://doi.org/10.1016/j.biopsycho.2022.108386
Ramirez, Jan-Marino. “The integrative role of the sigh in psychology, physiology, pathology, and neurobiology.” Progress in brain research vol. 209 (2014): 91-129. doi:10.1016/B978-0-444-63274-6.00006-0
Simpkins, C., & Yang, F. (2022). Muscle power is more important than strength in preventing falls in community-dwelling older adults. Journal of Biomechanics, 134, 111018. https://doi.org/https://doi.org/10.1016/j.jbiomech.2022.111018
Orr, R., de Vos, N. J., Singh, N. A., Ross, D. A., Stavrinos, T. M., & Fiatarone-Singh, M. A. (2006). Power Training Improves Balance in Healthy Older Adults. The Journals of Gerontology: Series A, 61(1), 78-85. https://doi.org/10.1093/gerona/61.1.78