As we come to the end of Autumn, the trees are barer, the evenings are darker and we are moving towards the cold winter months ahead. It’s usually a time of year where we slow down and spend more time in doors, some missing the summer outdoor evenings, others welcoming the quiet nights in. This year- having spent much of the summer under lockdown restrictions some of us may be left feeling confused and uncertain about what the winter may bring.

Some people love winter time, for others the darker and shorter days can be challenging. To those of you we say, try to see the positives. The cosy nights under fluffy blankets, candle lit movie nights with a nice warm hot chocolate – try to embrace these little comforts or find some of your own.

Sober October is coming to an end- well done to all of those who took part and raised money for charity! Perhaps this is a time to check in with yourself, reflect on the month and what it brought up for you. How did you feel? Did you still venture out (if the local rules allowed)? And if so, what was your alcohol free drink of choice? If you did not take part in the challenge, this piece will still be relevant. Let’s talk about hydration!

Alcohol

The general recommendation for fluid intake is 2L for females and 2.5L for males (1). Alcohol is the only fluid that does not count towards fluid intake. One reason why- because alcohol is a diuretic- it causes increased urination which can disrupt our hydration status (1). One study demonstrated every gram of alcohol consumed increased urine output by 10ml (2). That can add up to a lot of fluid over the course of an evening when you consider that 100ml of a 12.5% wine has 10g of alcohol. Alcohol induced ‘hangovers’- although still not fully understood- are considered to be somewhat attributed to dehydration (3). If you ditched the alcohol this month how did you feel? It’s likely that you felt more refreshed the next day- one reason likely being that you didn’t filter out all those hydrating fluids you drank throughout the day.

Tea & Coffee

Tea and coffee contribute to our fluid intake if not drunk in excessive amounts. Caffeine, the psychoactive component present in tea and coffee, also has a diuretic effect on the body (2). For the general population this does not disrupt hydration, but for those who consume more than 600mg of caffeine per day- it may impact fluid balance (fluids in = fluids out). Let’s have a look at some general estimated caffeine contents to put that into context.

 

Drink

 

 

Estimated Caffeine Content (mg)

Black Tea

75

Decaffeinated Tea 10
Green Tea 25
Instant Coffee 100
Filter Coffee 140
Single Espresso 75
Regular Americano 150
Regular Cappuccino/Latte

150

Large    Americano/Latte

225

Flat White 150
Decaffeinated Coffee 7

The European Food Safety Authority conclude that for healthy adults, 400mg of caffeine per day is generally safe. For pregnant women intakes of 200mg are considered safe. What does your daily caffeine intake look like? Remember, even if you don’t think you drink enough water- your teas and coffees could make up for it, once it doesn’t go over that 600mg caffeine limit.

As well as looking at the fluids in terms of hydration- lets look at the claimed health benefit of some common drinks. As it’s the season for warming drinks, we chose to do a little research on turmeric lattes, green tea and peppermint tea.

Turmeric Lattes

Some websites claim that turmeric lattes ‘boost your immune system’ and that turmeric itself is a ‘superfood’ with anti-oxidant, anti-inflammatory and antibacterial properties that can treat arthritis, fight colds and reduce flu symptoms. Sounds too good to be true, doesn’t it? While adding turmeric to your drinks and dishes can add delicious flavour, it’s unfortunately very unlikely to deliver a cure for anything.

What does the evidence say then?

The above claimed benefits are likely related to curcumin- a polyphenol present in turmeric. In order to achieve any benefits, curcumin would be needed in a concentrated dose ie a supplement rather than a couple of spoons of turmeric.

Curcumin is reported to support the management of oxidative and inflammatory conditions, arthritis, anxiety and high cholesterol and is also reported to offer health benefits for ‘healthy’ individuals. Previously the main barrier to it’s use was that it was poorly absorbed by humans, however scientists have discovered that combining curcumin with piperine (active component in black pepper) increases it’s bioavailability significantly- making it easy to absorb (4).

Curcumin is considered an anti-oxidant. It binds itself to ‘free-radicals’ (destructive components than can damage our cells) therefore reducing cell damage. Inflammation has been found as a contributing factor to many diseases including Alzheimer’s, cardiovascular disease, cancer and metabolic syndrome. Curcumin has been seen to supress inflammation, however there is no evidence to suggest it can prevent any of these conditions.

Curcumin supplementation has been seen in studies to reduced pain and increase physical function in individuals with arthritis (5).

Studies have also found that specific curcumin supplementation doses have been seen to reduce muscle soreness after exercise and in ‘healthy’ individuals as well as have the potential to reduce anxiety (6, 7).

So, while drinking a turmeric latte will not lead to any miracle cure when you dig deeper and unpack it, there are some potential benefits in curcumin supplementation (8).  Turmeric lattes are generally made using milk- so although you may not get significant antioxidant and anti-inflammatory benefits they are tasty and can be a good source of calcium, phosphorus, B and fat-soluble vitamins.

 

Green Tea

Green tea is also claimed to be a ‘superfood’ and is said to reduce risk of cancer, Alzheimer’s, CVD, diabetes as well as promote weight loss and help us to live longer. Green tea is also often thought to be free from caffeine- however this is untrue. Although it contains significantly less caffeine that black tea, it still contains about a third of the amount

Are there really benefits to drinking green tea?

Green tea is generally considered to have health benefits due to the presence of epigallocatechin gallate (EGCG), a type of antioxidant. There is some evidence from observational studies (not clinically controlled studies) that high green tea consumption may have a negative relationship with ovarian and colorectal cancer. But it is important to note that there could be many other factors influencing this. For example, these type of studies may not be able to control or consider all other lifestyle and diet factors such as smoking or veganism for example.

Most studies that look at the health effects of green tea are based in Japan and China, meaning the results cannot be considered to be applicable in Western societies. Other studies have found that green tea consumption increased risk of prostate cancer, again these studies were not controlled, meaning these studies do not show cause and effect. There is some limited evidence that green tea consumption or EGCG supplementation can reduce blood pressure and cholesterol- however this depends on the amount and the number of servings, and not all the results in studies are consistent.

So far there is not enough scientific evidence to recommend green tea as a way to reduce cancer or cardiovascular disease risk (9).

What about weight loss?

Long story short- green tea or green tea extracts have been found to have little or no effect on weight loss (10).

Is there a risk with drinking too much?

Green tea extracts have been associated with increased liver enzymes, insomnia, nausea, diarrhoea and increased blood pressure. It’s recommended that we do not consume more than 338mg of EGCG per day from supplements of 704mg EGCG per day from green tea, which equates to approximately 4 cups (9).

Peppermint Tea

This is another drink that is widely consumed and it is claimed to treat stomach pain/discomfort, aid digestion and relieve nausea and vomiting. Although people often report that peppermint tea can relieve gastrointestinal symptoms, including some symptoms of IBS (bloating, abdominal pain), there is not enough solid evidence to make a recommendation.

There is some research to show that peppermint oil, which can be taken in capsules, is effective at treating gastrointestinal symptoms of IBS in adults (11). One meta-analysis (looking at 4 studies using peppermint oil) found that peppermint oil supplementation did reduce IBS symptoms for a large proportion of participants (12). However, the trials were not blinded, meaning participants may have been aware of the treatment they were receiving and so this may have lead to bias (eg. if they had previously read about the effect of peppermint oil.

At present it is believed that the active ingredient in peppermint oil,I-menthol, has the ability to relax the smooth muscles of the intestine, support normal gut transit time (time it takes for food to pass through the gut) and promote gas expulsion and prevent gas formation (13, 14).

In conclusion, there is some evidence to suggest that peppermint oil supplementation can give symptom relief in IBS. It’s possible that it could relieve gut symptoms in those without IBS, however there is insufficient evidence to determine this. There are currently no clinical trials to demonstrate the effects of peppermint tea on gut symptoms. It is reasonable to think that because peppermint tea also contains some I-menthol, it could give some relief to abdominal pain and bloating, however there is currently no evidence to make a recommendation. Adverse reactions to peppermint tea are not widely reported, so it could be worth a try to see if this works for you (14).

We hope you enjoyed this piece and are able to take something away from it. Being more aware of your fluid and caffeine intake can be helpful to support a healthy lifestyle. We urge and encourage you to challenge the health claims you read online and to think critically about the nutrition ‘facts’ you hear. If something sounds too good to be true- it probably is.

We’ve mentioned before about having a holistic view on our diet and health- although foods contain anti-oxidants or have anti-inflammatory properties- this does not mean that if you focus on including that one food/drink you will reap the rewards of a body free of disease and inflammation. Again, we challenge you to dig deeper when you read about certain foods, drinks or products. Please share this article with your friends and let us know what you think. Please remember to always consult your doctor before starting to take any supplements, especially if you take other medications. Have a wonderful November.

The Sunlight Nutrition Team

Article written by Katie O’Callaghan

References

  1. Polhuis, K., Wijnen, A., Sierksma, A., Calame, W., & Tieland, M. (2017). The Diuretic Action of Weak and Strong Alcoholic Beverages in Elderly Men: A Randomized Diet-Controlled Crossover Trial. Nutrients9(7), 660. https://doi.org/10.3390/nu9070660
  2. EFSA Panel on Dietetic Products, Nutrition, and Allergies (NDA); Scientific Opinion on Dietary reference values for water. EFSA Journal2010; 8( 3):1459. [48 pp.]. doi:2903/j.efsa.2010.1459.
  3. Celeste T. Tipple, Sarah Benson and Andrew Scholey*, “A Review of the Physiological Factors Associated with Alcohol Hangover”, Current Drug Abuse Reviews (2016) 9: 93. https://doi.org/10.2174/1874473710666170207152933
  4. Shoba G, Joy D, Joseph T, Majeed M, Rajendran R, Srinivas PS. Influence of piperine on the pharmacokinetics of curcumin in animals and human volunteers. Planta Med. 1998 May;64(4):353-6. doi: 10.1055/s-2006-957450. PMID: 9619120.
  5. Hewlings, S. J., & Kalman, D. S. (2017). Curcumin: A Review of Its Effects on Human Health. Foods (Basel, Switzerland)6(10), 92. https://doi.org/10.3390/foods6100092
  6. Drobnic, F., Riera, J., Appendino, G., Togni, S., Franceschi, F., Valle, X., Pons, A., & Tur, J. (2014). Reduction of delayed onset muscle soreness by a novel curcumin delivery system (Meriva®): a randomised, placebo-controlled trial. Journal of the International Society of Sports Nutrition11, 31. https://doi.org/10.1186/1550-2783-11-31
  7. Sharma RA, Euden SA, Platton SL, Cooke DN, Shafayat A, Hewitt HR, Marczylo TH, Morgan B, Hemingway D, Plummer SM, Pirmohamed M, Gescher AJ, Steward WP. Phase I clinical trial of oral curcumin: biomarkers of systemic activity and compliance. Clin Cancer Res. 2004 Oct 15;10(20):6847-54. doi: 10.1158/1078-0432.CCR-04-0744. PMID: 15501961
  8. Hewlings, S. J., & Kalman, D. S. (2017). Curcumin: A Review of Its Effects on Human Health. Foods (Basel, Switzerland)6(10), 92. https://doi.org/10.3390/foods6100092
  9. The Global Resource for Nutrition Practice (2020) Functional Fods/Nutraceuticals- Green Tea. Summary of Recommendations and Evidence.
  10. The Global Resource for Nutrition Practice (2017) Weight/Obesity- Dietaty Supplements. Key Practice Points
  11. The Global Resource for Nutrition Practice (2018) Gastrointestinal System- Irritable Bowel Syndrome. ‘Does the consumption of peppermint oil reduce symptoms of irritable bowel syndrome?
  12. FordAlexander C, Talley Nicholas J, Spiegel Brennan M R, Foxx-Orenstein Amy E, Schiller Lawrence, Quigley Eamonn M M et al. Effect of fibre, antispasmodics, and peppermint oil in the treatment of irritable bowel syndrome: systematic review and meta-analysis BMJ 2008; 337 :a2313
  13. The Global Resource for Nutrition Practice (2018) Gastrointestinal System- Irritable Bowel Syndrome- Summary of Recommendations and Evidence
  14. McKay DL, Blumberg JB. A review of the bioactivity and potential health benefits of peppermint tea (Mentha piperita L.). Phytother Res. 2006 Aug;20(8):619-33. doi: 10.1002/ptr.1936. PMID: 16767798.