Water – No Need To Overdo It

As part of my research for the Live Forever Manual I thought drinking plenty of water would be an obvious tip, but the evidence wasn’t clear enough that it extended life. So it hasn’t made it as a practical tip in the book, though there are plenty of benefits from keeping well (but not overly) hydrated.

The 8 glasses of water per day rule came from a 1945 recommendation stating that a suitable water allowance for adults is 2.5l/day in most instances. However internet, sports and nutrition media tend to present these quantities as plain water ignoring the fact that most of those fluids are regularly consumed in everyday meals and drinks. One of the probable reasons for hydration becoming a popular issue presented by media and regulatory bodies was the increase in the consumption of caloric beverages, which has contributed to obesity prevalence worldwide. This isn’t an issue in the UK, as one epidemiological study found that total fluid intake was mostly comprised of hot beverages, followed by water.

water - no need to overdo it

Water certainly is an essential component of our diet in so many ways. Firstly, it controls body temperature through fluid loss (sweating). The second essential feature is regulation of kidney function as kidneys use water to filter waste from the bloodstream and excrete them via urine.

Some smaller-scale studies also found that bad hydration may be linked with adverse cardiovascular health as it is involved in regulation of blood volume which is closely associated with blood pressure and heart rate. Blood volume is tightly regulated by the water intake/output ratio, which means that loss of body water will also decrease the blood volume, that way affecting other elements of the cardiovascular cascade.

Although gastrointestinal health is largely affected by bad dietary habits, it is also seen that inadequate water intake is a common culprit in constipation problems. Enhanced water intake is recommended in those problems as it can enhance gastrointestinal transit, however, evidence suggests that people respond differently. That is because some people are in hypo-, hyper and euhydrated state. The only usefulness of this treatment is seen in individuals that are in hypohydrated state not in those that are well hydrated.

Large observational studies found that water deprivation may affect cognitive performance, impair concentration, increase irritability and prolong migraines. The mechanisms underlying the associations between water intake and cognitive performance are not well studied, but there are indicators that mild dehydration may physiologically stress the body and compete with cognitive processes. it has been proposed that mild dehydration acts as a physiological stressor which competes with and draws attention from cognitive processes.

Skin health and moisture is often linked with proper water consumption, and this was confirmed in clinical trials in which 2L of mineral water/day had an impact on these features. Again, the significant results were obtained in the group that was already less hydrated and not in people that were euhydrated.

It is noteworthy to mention that water requirements vary greatly depending on the climate zone (people living in hot climates have higher requirements than those living in colder temperatures), while there is also a big difference between sedentary people and those performing some physical activity. People who have regular exercise in hot conditions and no adequate fluid replacement are at higher risk of hyperthermia, reduced stroke volume and cardiac output, while they also tend to experience decreases in blood pressure and reduced blood flow to muscle.

Yes, reasons for good hydration are plenty, however, a lamp of evidence reports conflicting results, that way suggesting that recommendations and alarms from the media are overreacting. Large population-based studies do not support the notion that we should drink 2 or more litres of water per day. As a matter of fact, one of them concluded quite the opposite – women that drunk higher amounts of water had a lower survival rate than those drinking less. One population-based cohort also failed to confirm that high water intake may lower the risk of kidney dysfunction and cardiovascular diseases in older adults (average age of 70.3), nor in men aged 55-75. But in another large-scale study they found a significant negative association between water intake and the risk of fatal coronary heart disease (which was more pronounced in men), while women with higher intake of fluids other than water were more likely to become ill.

Finally, animal-studies data were pointing out that inadequate urination may prolong the contact time between carcinogens and urothelium thus enhancing the risk of bladder cancer occurrence. One large-scale prospective study supported the notion that men should drink 2.5 l of water daily in order to lower the risk of bladder cancer.

So, according to the science we should definitely pay attention to our hydration status, however, bear in mind that you consume fluids through your regular diet too.

Sofa exercises mean you don’t have to be sedentary while watching TV

If you’ve got a desk job and enjoy films and TV dramas then you’re at a big risk of not moving around enough every day. Research shows that being a weekend warrior (1-2 big gym sessions a week) is not as good for your longevity as regular movement every day.

If you’re watching live TV with commercial breaks then that is the ideal time to get up and move around – maybe a few quick walks up and down the stairs or through your apartment.

And if there aren’t any breaks that’s not an excuse either! I’ve found a few useful sofa workouts that can be done at the same time as watching TV.

With these it’s possible to perform a good mix of abs, legs and upper body exercises. Here are 4 of my favourites:

  • Seated scissors
  • Couch crunches
  • Chest squeeze
  • Sofa dips

sofa exercises
I’m not suggesting these routines count towards your (minimum!) 150 minutes of moderate exercise per week – but they will make sure you keep moving around even when not moving about.

See these websites for full work out details:
DAREBEE – excellent selection of workouts including cardio sofa and sofa abs
Holmes Place – 6 exercises you can do from the sofa, including the most chilled side plank ever!
BuzzFeed – 12 station circuit with animated GIFs demos
ChicagoTribune – 5 exercises you can do without upsetting your inner couch potato

All round health trackers for under £100

Do you want to track your general health? Me too, so I had a look around for some fitness trackers that might do the job – but when I reached 40 prospective devices I realised this was a bigger job than expected. The boom in health wearables at the moment seems to cover both ends of the market – from basic step counters to improving fitness with a personal trainer on your wrist. Some of these look fantastic but are out of most people’s budget.

So let’s focus on what features are really useful in a health tracker. And note that I’m saying health tracker as opposed to fitness tracker, as I want to monitor physical characteristics that might have real impact on my life expectancy.

Two important measurements to keep a close track on are blood pressure and weight, and although there are a couple of wrist BP monitors available they’re more aimed at people with a medical condition rather than as a convenient wearable, so I’ll continue doing that with separate equipment for now.

The three key physical properties I want to track are:

  • inactivity
  • sleep
  • resting heart rate


There is more and more research highlighting that long periods of inactivity (for example at a desk or watching TV) cannot be compensated for with a few high intensity gym sessions. In one study of over 50s those with the lowest level of activity were 3 times more likely to die than those with average activity levels over an 8 year period.

For me this puts inactivity alerts as the number one feature required in a wearable health tracker. It’s no use reviewing your activity at the end of the week; I need a gentle nudge there and then to remind me if I’ve been sitting for too long.


Another area of your life that has a definite impact on your life expectancy (and that you can control) is the amount of sleep you have each night. Most people know that too little sleep is bad for them, but too much is even worse. In a large meta-study it was found that people sleeping less than six hours a night were 12% more likely to die prematurely, however for those sleeping more than 9 hours a night there was a 30% increase.

Resting Heart Rate

The American Heart Association considers the resting heart rate as a good indicator of general fitness because a lower rate demonstrates that the heart muscle doesn’t have to strain to maintain a steady beat.

A normal resting heart rate (ideally measured before you get out of bed) is between 60 and 100 with professional athletes going down to 40 and below. Mine averages 59 (when taking my monthly blood pressure measurements) and it looks like you should be targeting the lower end of the 60-100 range, but if you’ve got a low heart rate and are having dizzy spells then best to see a doctor.

Almost all fitness trackers that include a heart rate monitor are using an optical sensor. These aren’t as accurate or responsive as chest straps that use electrical activity, especially when measuring heart rate during intense exercise, but for long term averages and morning resting rate they’re generally considered OK. Saying that, one of the products picked uses bioimpedance sensors so may be just as accurate as a chest strap, I’m not sure.

Product Comparison

With these 3 key tracking requirements, and a budget of £100 (about US$130), there were only 3 products from my long list that made the grade.

  • Jawbone Up3 (£59)
  • Sony SmartBand 2 (£79)
  • Xiaomi Mi Band Pulse (£39)

Surprisingly none of the Fitbit range met the criteria as the Alta has inactivity alerts but no HR monitor and the Charge HR is the opposite. Be careful when reviewing the Charge HR – they hint at an inactivity alert but it’s only on the app for post-review, not built into the device itself.

Product Price Temp (skin) Battery Life Display Phone alerts Water-poof Weight (g)
Jawbone Up3 £60 Y 7 days 3 LEDs N Splash 29
Sony SmartBand 2 £80 N 5 days 3 LEDs Y 3m 25
Mi Band Pulse £39 N 7 days 3 LEDs Y Splash 14


Jawbone Up3


Jawbone Up3

The Up3 comes in 2 styles (twist and cross) and half a dozen different colours, but more importantly it come packed full of sensors.

Unlike pretty much all other activity trackers and smart watches, the Up3 uses bioimpedance sensors to measure heart rate. The sensors measure the resistance of skin tissue to tiny electric currents. For more technical information refer to their blog post: https://jawbone.com/blog/up3-advanced-multi-sensor-technology/

It says it tracks REM sleep – not sure how, I assume using an algorithm based on heart rate and movement – I’ll investigate this more when I get my hands on one (it’s on my xmas list!).

A feature I particularly like, and possible essential, is being able to configure the inactivity reminder – you can set the duration before receiving a vibration alert using the app and also set the time window when it monitors this. Makes sense, not sure how others do it when you’re sleeping.

Until I get to try one myself, here’s some feedback from the Wareable review (3.5 stars):
•    comfortable fit, though clasp is fiddly as anything
•    sensors leave imprints on your skin – but not uncomfortable
•    app is one of the most comprehensive out there
•    charging cable is badly designed
Read full review on Wareable: http://www.wareable.com/jawbone/jawbone-up3-review

Sony SmartBand 2


Sony Smartband 2

Available in 4 swappable colour silicone bands the SmartBand 2 looks as stylish as you’d expect from Sony. It lacks a few sensors included in the Jawbone Up3 however it does add vibration and LED alerts for phone notifications as well as basic media controls for pausing and skipping music.

The biggest complaint appearing in several reviews is the accuracy of the step tracking – with reviewers notching up steps when the phone isn’t being worn and over 1000 steps while sleeping.

An important note is that on the Sony website it claims 5 day battery life, but that is only in stamina mode with the heart rate sensor turned off, so I’ve put the more realistic 2 day battery life in the comparison table.

Key points from the Wareable review (3 stars):

  • old school fitness band design
  • smart alarm can wake you during light sleep once you’ve set certain parameters
  • uses 2 apps – one for settings and on the spot readings, then the Lifelog app for activity graphs, milestones, etc
  • battery life could be better

Read full review on Wareable: http://www.wareable.com/sony/smartband-2-review

Xiaomi Mi Band Pulse


Mi Band

Not to be confused with Mio Global (who invented the optical heart rate sensor) the Mi Band Pulse is the budget option but retains most of the features offered by premium brands.

The heart rate monitor checks your pulse every 10 minutes, or on demand, and takes up to 30 seconds to take a reading so isn’t designed for fitness tracking at the gym, but should work fine for checking your resting heart rate first thing in the morning.

The Mi Fit app is also suitably budget, however it is compatible (with limited functionality) with both Google Fit and Apple Health.

The main reason I didn’t choose the Mi Band Pulse is the inactivity alert. Although it has one, it’s not configurable, so only reminds you have sitting still for an hour – I’d like to set mine to 30 minutes.

Key points from the Wareable review (3 stars):

  • basic design
  • breaks your walking and running into blocks of active time
  • sleep tracking is hit and miss
  • notifications for up to three apps

Read full review on Wareable: http://www.wareable.com/xiaomi/xiaomi-mi-band-pulse-1s-review