Tuesday, February 27, 2007
Contrary to popular wisdom there is a dearth of scientific evidence to support the health benefits regularly touted for drinking huge amounts of water. And by strange coincidence, a lot of research that does support it has been sponsored by companies who market the bottled version.
In fact drinking more water than your kidneys can filter dilutes your blood, reversing important osmotic processes, eventually putting you into a coma. Jennifer Strange (yes, really) had taken part in a "Hold Your Wee for a Wii" (again, yes, really) game on an American radio station. Afterwards she reportedly said her head was hurting and went home, where she was later found dead. Initial tests have shown her death is consistent with water intoxication.
However, a healthy adult's kidneys can comfortably handle about a litre of liquid per hour, so this is unlikely to be a problem for most people. In fact, many people could do with introducing more liquid into their diet.
Not ingesting enough liquid prevents the liver and kidneys from functioning properly, resulting in a wide range of symptoms, including:
Thirst (yes, really), restless or irritable behaviour, decreased skin turgor, dry mucous membranes and sunken eyes... moving on to, constipation, flushed face, dry, warm skin, dizziness, weakness, cramping in the arms and legs, lack of concentration, headaches, dry mouth and tongue with thick saliva.
How much liquid we need varies, depending on body size, activity levels and environmental conditions, but 1.5 litres a day is a basic yardstick. This doesn't all have to come from water, it can come from our food (especially fruit), soft drinks, tea, coffee and even (hurray!) alcoholic drinks. Of course, caffeine and alcohol are both diuretics, so the liquid will be expelled quicker, but liquid is liquid, your body will extract what it needs.
Any liquid that enters our stomach is absorbed only after it has been warmed to body temperature. So if you need hydrating quickly, warm drinks are actually better than cold (yes mum, tea is an excellent example).
If you can bear the taste of green tea, there is growing evidence that it provides a host of health benefits. I've tried to like it, really I have, but personally I'm going to have to find other routes to whatever advantages it offers!
There are benefits to drinking plenty of water:
1. It is calorie, alcohol, caffeine and acid-free.
2. It contains a wide range of beneficial minerals.
3. It keeps your stomach feeling 'full', helping avoid the urge to 'snack'.
4. It improves the efficiency of your digestive system.
5. It improves concentration levels.
6. It stabilises mood swings.
The colour of your urine acts as a good gauge of whether you are properly hydrated. Clear to straw-coloured is fine. Darker than this means you probably need more liquid. Also, frequency of 'loo-breaks' will soon tell you if you're drinking too much liquid. Once every couple of hours is fine, more than this means you're probably drinking too much. Of course, caffeine and alcohol will increase the 'loo-break' factor!
In Europe, standards for tap water are very high. So water (from the cold water tap) should be fine. However, my personal experience has been that some tap water tastes atrocious. Filtering the water can help, but make sure the filters don't remove minerals from the water.
My favourite bottled water is Pellegrino, I think it tastes great (my kidz HATE it, which is another bonus cos they don't steal it!), it has a balanced mineral content, and I've found that drinking it with my evening meal (instead of wine) means that I enjoy the taste of the food more, with the added benefit that my hunger isn't alcohol-assisted (yes, alcohol increases hunger by lowering blood-sugar levels).
I then have a glass (or three) of my favourite inky red as a dessert. Cheers!
at 9:19 am
Thursday, February 22, 2007
There was a time when long-distance messages arrived once (or twice) a day, delivered by a real person, to a real mailbox.
Then came the telephone.
Then the fax machine.
Then instant messaging.
Then RSS feeds.
Which is all well and good, but the plethora of conduits by which people can contact you (and by which you contact other people), can become a powerful procrastination tool (especially when there are things you need to get done, but really don't want to do!).
There are no hard-and-fast rules for how to deal with this. I need to check my email frequently during work hours, not so frequently at home. RSS feeds are things I browse during coffee breaks. If I find myself checking them every half-hour of a weekend, I know it's time to give myself a talking to!
There is a good chance that you already know whether you are exhibiting 'obsessive-compulsive' tendencies in this area... but as a guideline, if you are spending more time checking whether you have a text/ voicemail/ email than you spend reading them, you could probably scale the frequency down a notch!
at 9:02 pm
Tuesday, February 20, 2007
Joints are the bits that hold our bodies together. Some joints act as hinges (such as knees and elbows), while others allow for more complicated movement - a shoulder or hip joint, for example, allows for backward, forward, sideways, and rotating movements. And some don't move much at all.
Fibrous joints are the ones that don't move much. The dome of the skull is made of a number of bony plates. Between the edges of these plates are joints of fibrous tissue. Fibrous joints also hold the teeth in the jawbone.
Cartilaginous joints allow very limited movement. Each of the vertebrae in the spine is held together by cartilaginous joints. They give the spine its combination of strength and flexibility.
Synovial joints are filled with synovial fluid, which acts as a lubricant to help the joints move easily. There are three kinds of synovial joints that play a big part in voluntary movement:
Hinge joints allow movement in one direction, as seen in the knees and elbows.
Pivot joints allow a rotating or twisting motion, like the ones that support our head.
Ball-and-socket joints allow the greatest freedom of movement. The hips and shoulders have this type of joint, in which the round end of a long bone fits into the hollow of another bone.
at 8:39 am
Thursday, February 15, 2007
Muscles move things. They work with our skeleton to help move us around. They also help us chew our food, and move it through our digestive tracts.
The human body has more than 650 muscles, making up half its mass.
Humans have three different kinds of muscle:
Skeletal muscle holds the skeleton together, give the body shape, and help it with everyday movements. It is can contract quickly and powerfully.
Smooth muscle is controlled by the nervous system. Examples of smooth muscles are the walls of the stomach and intestines. Smooth muscle is also found in the walls of blood vessels.
Cardiac muscle comprises and powers your heart.
Muscles are controlled by the brain and nervous system. Smooth and cardiac muscles are controlled automatically by the brain and the upper part of the spinal cord called the brain stem. Skeletal muscles are voluntarily regulated by the parts of the brain known as the cerebral motor cortex and the cerebellum.
The motor cortex sends electrical signals through the spinal cord and peripheral nerves to the muscles, causing them to contract. The motor cortex on the right side of the brain controls the muscles on the left side of the body and vice versa.
The cerebellum coordinates the muscle movements ordered by the motor cortex. Sensors in the muscles and joints send messages back through peripheral nerves to tell the cerebellum and other parts of the brain what is going on.
Muscles move body parts by contracting and then relaxing. Your muscles can pull, but they can't push. So they work in pairs of flexors and extensors.
The flexor contracts to bend a limb at a joint. Then, when you've completed the movement, the flexor relaxes and the extensor contracts to extend or straighten the limb at the same joint.
For example, the biceps muscle, in the front of the upper arm, is a flexor, and the triceps, at the back of the upper arm, is an extensor. When you bend at your elbow, the biceps contracts. Then the biceps relaxes and the triceps contracts to straighten the elbow.
at 8:42 am
Tuesday, February 13, 2007
The adult human skeleton (or 'skellington') is made up 206 bones. The foetal skeleton starts as flexible cartilage, but within a few weeks it begins the process of ossification, as deposits of calcium phosphate and stretchy collagen are laid down.
A young human has zones called growth plates. These consist of columns of multiplying cartilage cells that gradually transform into bone. It takes about 20 years for this process to be completed.
Bone contains three types of cells:
Osteoblasts manufacture new bone and repair damage
Osteocytes transport nutrients and waste products
Osteoclasts sculpt and shape
Bones are composed of minerals including calcium, phosphorus and sodium, as well as a protein called collagen. Calcium is the stuff that makes your bones hard. Bones also act as a calcium store for the rest of the body.
In the centre of your larger bones there are groups of stem cells (bone marrow), which produce the body's red blood cells and platelets. Red blood cells carry oxygen to the body's tissues, and platelets contribute to blood clotting.
Bones are made up of two types of material
Compact bone is the hard, structural part of your skeleton. It is permeated by a complex matrix of tunnels, containing blood vessels and nerves.
Cancellous bone comprises the inner parts of bone. It is a spongy, mesh-like network, filled with red marrow, found mainly at the ends of bones, and yellow marrow, which is mostly fat.
Ligaments are fibrous straps that join your bones together.
Cartilage is a flexible, rubbery substance that absorbs shock and reduces friction where bones meet.
at 10:31 am
Thursday, February 08, 2007
The human brain is a marvellous and mysterious thing. Carrying out 24/7 monitoring and managing of thousands of body processes and capable of storing, organising and retrieving millions of items of information. And yet I regularly reach the top of the stairs and wonder what it was I had ascended them for. Or have a 'brilliant' thought during a long car journey, then realise that although I remember having the thought, I can't remember what it was. Or hear a song, like it, but - within minutes - forget what it's called, or who it's by.
Now I'm sure that neuroscientists will eventually find a logical explanation for this, and there may even be a day when there are ways of 'logging' your brain's processes. Until that day, we're stuck with more mundane methods of remembering things.
I've investigated and tried a lot of methods of making sure I don't forget things. Computers are helpful, mobile phones better... but probably the most useful tool in my 'don't forget' armoury are 12 x 8cm cards. And a writing implement. Pieces of card are cheap, require no power source, are rugged and disposable. And my brain's OCR equipment is brilliant at interpreting even the most illegible scribbles.
And by keeping to a 'one card, one idea' principle, they are easily filed or carried, then disposed once the task has been completed, or transferred to appropriate digital storage systems.
Now, where did i put that pen?
(This article was first published on my other blog.)
at 8:22 am
Tuesday, February 06, 2007
Our metabolic rate (the speed at which the little men in our body utilise our body's energy supplies) is determined by a combination of:
Genetics: Some people have a naturally faster metabolism. They're the type of people who can eat what they like and never get fat (you know, those unbearably smug people).
Age: As we leave our teens behind, our metabolism drops 2 per cent per decade. Yes, it's yet another reason for not getting older.
Muscle: Muscle cells use up 8 times more energy than fat cells. The more muscle we have, the faster our body will burn energy.
Exercise: Moving our body around burns energy. And depending on the type of exercise, it can raise our metabolic rate even after we stop moving around.
How often we eat: The eating and digestion of food raises our metabolic rate. If you go without food for an extended period of time (5 hours for males, 3 hours for women) those little men get twitchy, and start slowing your metabolism down.
Nutrition: Metabolic processes require a myriad of complex chemical reactions. To perform this process efficiently, our body needs a constant supply of nutrients and catalysts. If there is a shortage, our metabolism becomes inefficient and sluggish.
Speeding up our metabolic rate can be achieved by:
Exercise: ANY exercise is better than no exercise. However, the popular wisdom that aerobic exercise (walking/running/cycling) is the best way to speed it up has been challenged by recent research (more about that in subsequent blogs).
Eating regularly: Eat small, regular meals from the moment you get up until the moment you go to bed.
Eating good food: This helps to maintain a supply of appropriate nutrients which in turn keeps your metabolism working smoothly.
Drink plenty of liquids: I'm going to do a fuller blog on this soon, but keeping your body supplied with (non-alcoholic, low-sugar) liquids will help to keep your metabolism running. And, for those whose bodies are tolerant to it, caffeinated drinks (in moderation) will give it an extra boost!
I'll be expanding on these topics in later blogs.
at 8:21 am
Thursday, February 01, 2007
This is a tip that is particularly valuable if you are involved in a leadership role, but it can be applied to a very wide range of situations. It is simple, non-manipulative and common-sense. And it can save you (and other people) a lot time and emotional pain!
Scenario A: Someone approaches you with an idea/suggestion/project. After hearing what they have to say, you tell them you'll get back to them on it.
The person goes away with the assurance that you will contact them. You, being busy, either forget about it completely, or add it to the bottom of your (already lengthy) 'to do' list.
Two months later, the person is frustrated that you haven't got back to them. And you are dreading the phone ringing, or meeting them (and 17 other people you have made a similar promise to) in the street.
Scenario B: Someone approaches you with an idea/suggestion/project. After hearing what they have to say, you tell them TO GET BACK TO YOU on it.
The person goes away knowing that it is THEIR responsibility to get in touch with you about the idea. The beauty of this simple inversion is that if the idea is a whim, they will forget about it, giving you one less thing to do. If you say 'I'll get back to you', even if the idea is a whim, they will remember that you promised to contact them (and with some people, the grudge that you didn't will be nursed long after they have forgotten what the idea was!).
Of course, if their idea/suggestion/project is one that you think is worth pursuing, and they don't contact you, you'll get extra 'points' for contacting them.
at 8:44 am