Coffee: your friend or foe?

Coffee. It’s like the world’s favourite elixir. Mine included. For an athlete, there are many studies supporting its use as an ergogenic aid for athletes – helping reduce rates of perceived pain and effort, improving muscle fibre recruitment and enhancing glycogen repletion post-workout. These benefits are individual, however, and while research suggests that genetic differences in our ability to detoxify caffeine could account for this, it is not a universal finding. This is something true for athletes and non-athletes alike.

Other features of coffee are also salient for all individuals. Caffeine is ketogenic; not only can it help mobilise fatty acids to be used for energy, it increases the presence of ketones in the bloodstream – hence it is a good pre-workout fuel to help elicit fatty acid oxidation pathways and provide fuel for the workout in the absence of glucose. This doesn’t necessarily translate in additional body fat loss (more important lifestyle strategies are required for that, such as a caloric deficit, resistance training, reduction in stress etc), but can encourage these energy pathways to be upregulated, helping in the process of becoming adapted to a lower carb dietary approach.

Coffee improves insulin sensitivity and glucose tolerance (potentially related to the polyphenols present, though the mechanism is currently unclear), therefore enhancing the effects of both a lower carb approach, or a plan that includes fasting (either intermittent fasting, super-fasting, or a 5:2 approach such as the one in my fat-loss plans). Further, anyone doing my accelerated fat loss plans who have that 16h intermittent fast on the ‘fasting mimicking’ days could experience a more potent effect from the fast by including black coffee alongside water as their beverages of choice.

Autophagy, where our body starts to clear out damaged cells from the liver, heart and muscle tissue, is one of the benefits of fasting as you know. In mice models it might take just 16 hours for this to occur, in humans it is likely to take a lot longer given the differences in our metabolic rate (a mouse has a faster metabolism). Consuming caffeine on an empty stomach (or as part of a fast) promotes autophagy, which theoretically would shorten the time that is required to fast to stimulate this process. It also triggers AMPK, an enzyme that inhibits fat storage, promotes fat burning and activates antioxidant networks. These properties are thought to underpin much of the purported health benefits of drinking coffee.

It IS a balance though – if you’re following a fasting protocol, working out, and reading this at 3.30am in the morning, it’s a good sign that your brain is wired – raising cortisol to the extent that it’s (quite obviously) disrupting sleep. When we fast, like exercise, it places a stress on the body – this is where many benefits come from, as your body responds and adapts, becoming more resilient. However, too much of anything is too much! If coffee on top of your fasting regime or exercise program (or, life in general) is causing this stress response, then it is worth dialling it back a bit (or go 1/2 and 1/2 with decaf) to see if this changes your stress response.

Caffeine (or coffee), though, may not be good for anyone with gut issues. As it can stimulate the stomach cells to release more gastric juices, aiding in digestion, we often hear that too much coffee promotes a highly acidic environment and as such, could increase the risk of damage to the cells and subsequent gut issues. The literature, though, reports that caffeine does not negatively impact gastric or duodenal ulcers, and in fact when administered in vitro, could help repair cells damaged by inflammatory bowel conditions such as ulcerative colitis, and is also protective for the mucosal layer of the gut. Research suggests this is because caffeine increases blood flow to the gastrointestinal tract. Conversely, caffeine can lower the tone of the oesophageal sphincter – the valve that controls the release of stomach acid into the oesophagus, thus may promote heartburn and reflux.

With all research studies, it’s important to remember you are your own best investigator when it comes to how coffee affects you. I’ve said this before, but a good point to reiterate. The best advice, then, is to pay attention to how you feel when you drink coffee. Does drinking coffee make you more wired, especially when you fast, indicating it stimulates your stress (or cortisol) response? Does it give you reflux or heartburn? Does it upset your digestive tract more than settle it? Everyone has a different tolerance level to coffee, and further, our ability to detoxify it may also be different. If you feel great when you have coffee, and you don’t have any gut-related issues, then it is likely absolutely fine for you. If you notice an irritated gut, or you feel a bit wired, then it isn’t worth persevering with coffee for the purported health benefits – in your case, it might be making things worse.

coffee2

Ahhh… coffee 🙂

Shift work and health: the Cliff notes.

I’ve worked in a wide variety of jobs in my life. Like many people, I spent the latter part of my high school and university years cleaning toilets, clearing tables, washing dishes, delivering pizza and making sandwiches when there was only one sandwich maker in town. Subway, George St. Aaah….the memories. Somehow I was always put on the graveyard shifts of Thursday night 8pm-4am and Saturday 10pm-6am. Though it totally went against my natural tendency to be early to bed, early to rise, they were the most fun shifts to work. As one of the few places open 24 hours over the weekend, we got queues out the door of students either rolling in from the Cook or stumbling home from KCs, with the busiest period being from 2.30am to around 4am. I still remember the excitement at serving both a glazed eyed Marc Ellis and Rachel’s brother Jonathan from Shortland Street – before seeing Shorty stars was as ho-hum as …. seeing Shorty stars. Anyway. I’d get home either 4.30 or 6.30 and sleep 5ish hours before getting up and try to get back into a daytime routine. I always felt rubbish through lack of sleep and so thankful that I wasn’t pursuing a career that required me to do shift work.

Now, though, amongst the industries that have always needed to be available 24/7, the global society we live in now necessitates other occupations to put in hours that extend beyond the 9-5. The prevalence of employees working shifts in the media, healthcare industry, on the front line and in the corporate world is estimated to be around 20% and the available data in New Zealand is in line with this. This is a large subsection of the working population, and why it’s of note is that there are well established links between shift work and poorer health outcomes – both short and long term. The constant sleep deprivation that results from shift work is a major underlying issue.

The most important things we can do to help mitigate the effects of chronic sleep deprivation that occurs due to shift work (aside from actually sleeping!) are the very things that go out the window. A regular exercise routine is more difficult to maintain, due to tiredness from lack of sleep or the inability to structure if you are on a shift cycle that changes from day to night. Eating healthily is more difficult as having motivation to plan and prepare is more challenging, and often the pull to higher sugar, poorer nutrient foods is governed by cravings and accessibility. In addition, perhaps overlooked, maintaining relationships can be more difficult as the non-sociable hours of shift work impact on our availability to spend time with friends and family. Hanging out with John on the 5th floor is not the same.

It’s also well established that the affects on circadian rhythm put shift workers at a higher risk of many chronic diseases. Up until 150 years ago we were constrained by the natural sunrise and sunset and life on earth had evolved according to this. When artificial light was invented there were suddenly more hours in the day that could be spent being awake, and the shift in our wake and sleep cycle impacts on metabolism, hormones, digestion, cardiovascular system; in fact all of our cells in our body is affected by this. Sleep deprivation in the short term increases insulin resistance – it takes just a single nights’ sleep for this to occur. There is an increase in the risk of injuries on the job, and a link between both acute and chronic gastrointestinal problemsMood disorders are also associated with circadian rhythm disruption, and both observational and experimental data point to an increased risk of obesity in shift workers due to these circadian rhythm changes.  Over the long term, there is an increased prevalence of risk factors associated with the metabolic syndrome, type 2 diabetes, cardiovascular disease and cancer are all seen in shift workers compared to those who keep a more normal work schedule.

While you might think people who are early risers would be more negatively affected by shift work, this hasn’t been found to be the case.  Research shows that those who are late risers have lower levels of melatonin (a hormone that mediates the sleep-wake cycle); the suppression of which is one proposed mechanism for the increased health risks associated with working hours that disrupt circadian rhythm.

So what to do? Obviously, being able to opt out of shift work is not realistic for the 20% of the population who live and work in this 24 hour society. This report details the interventions in the research setting that have been found to be most beneficial. These include scheduling shifts to be ‘forward’ shifts rather than backward shifts (i.e. moving from a morning, to an afternoon, to an evening shift), avoiding stimulants such as coffee (in excess) and wearing light blocking eyeglasses on the way home from night shift. Sleeping in a dark room and wearing an eye mask will also help.

Along with the above, ensuring good sleep hygiene practices through both diet and exercise are essential. Though it might be the last thing you feel like doing if you’re just getting into exercise, a routine that you stick to will go a long way to helping you mitigate these effects. Exercise is so important for everyday health and well being, that to ignore it would only further exacerbate some of the health issues mentioned above. Further, in the face of sleep deprivation and acute insulin resistance, strength training helps improve insulin sensitivity and may minimise the blood sugar disruptions experienced. As mentioned, coffee is likely one of the first things you go to when you feel like you need an energy hit, but instead of this, why not try green tea – it has L-threanine in it which helps keep you alert without the caffeine hit. Perhaps save coffee for your days off (and limit to just one); dare I say it – try a decaffeinated brand otherwise. Some companies like to supply food for their employees, and this tends to be cheap plain biscuits, white bread and jam, and other types of food to provide a quick hit of energy when time is of the essence and there is no time to stop for a real meal. These options, along with the vending machine, are the last foods you want to be eating. On your off days make it a habit to prepare two or three ‘dinner’ like meals that you can freeze and eat throughout the week. Trying to structure your whole food, minimally processed meals so they are ‘dinner’ like at dinner time (before you head into a night shift, perhaps), lunch like in the middle of your shift, and then a lighter meal before you hit the sack in the morning will maintain the regularity of meals regardless of whether you’re working or not. Being prepared with your good food options means you can avoid those that are available at work. In addition, a magnesium supplement (with an amino acid or citric acid chelate) before bed can help promote good sleep. Finally, if you are constantly waking up, practicing some deep breathing in bed can help calm you down and send you back to sleep. Diaphragmatic breathing will decrease your sympathetic nervous response – ‘fight or flight’ and the levels of stress hormones entering the bloodstream which are released because of this which could prevent you falling easily back to sleep.

Shift work is a necessity for many people, and some fare better than others. If you are a shift worker who fares fairly well despite the disruption in sleep and subsequent poor lifestyle habits you may not feel that these tips would apply to you. However maintaining your health is as important now to offset the long term effects of shift work.