How To Lose Weight

There is a lot of nonsense written about how to lose weight, so I have been browsing a variety of authoritative-seeming books on diet and exercise in an attempt to resolve all the claims and counter claims. Here is a summary of the advice that seems to be solid:

Run a small energy deficit: The most important thing is to burn up more energy (calories, joules) than you ingest. It is impossible not to lose weight if you do this. The body will have to find energy from somewhere and it will turn to its fat supplies to do this. However, it's best not to run a high deficit because then the body thinks there's a famine happening, and starts reacting in counterproductive ways. So slowly is best.

Do aerobic exercise: Thirty minutes three times a week has been shown to improve health dramatically. In terms of weight loss, it adds to the energy burn, which is helpful.

Build up muscle using weights exercises: The amount of energy you burn just moving around normally during the day is partly dependent on the amount of muscle you have. So if you build muscle, you'll burn more energy during the day and this will assist you to run an energy deficit. So do some weights exercises to increase muscle mass. Be sure that your diet includes enough protein to help build the muscles.

Increase lifestyle activity: Change your lifestyle habits so as to introduce some additional activity. Even the smallest change can add up to a lot over a long period. For example, if you live near to where you work you could walk to work each day instead of driving. If you live a long way from work, get off the bus a few stops early and walk the rest of the way. Take the stairs instead of the escalator (or climb the last few floors to your office). Little things like this, when applied over a long period, can have a big impact. Increasing lifestyle activity is probably the easiest way to lose weight.

Get real about snacks: I remember reading somewhere that when overweight people were asked to keep logs of what they ate, the logs actually didn't look too bad. However, a closer look revealed that the logs omitted about 30% of energy input in the form of unlogged snacks! So it seems that overweight people often delude themselves into thinking that they are eating normally by having normal or even small meals, and then snack on high-fat snacks throughout the day. Regardless of whether you consider snacks to be a good thing or a bad thing, it's important to acknowledge all  food intake during the day, not just the "official" meals! The capacity of unacknowledged snacks to impact on weight is one example of the general principle that weight management is a long term game of competing rates (rate of calorie input and output), and even a small adjustment can have a huge effect over the long term.

Have a big breakfast: This is a really important one for a variety of reasons. First, studies have shown that the body gets a better shot at burning up energy if it is provided early in the day rather than late in the day. I haven't researched the details, but, as I understand it, if you eat a big breakfast, the body will tend to circulate the energy within your body and burn the energy during the day, whereas if you have a big dinner, your body will tend to spend your sleeping time storing all the energy in a more permanent form, in which it is less likely to be burnt the next day. The second reason for having a big breakfast is hunger management. If you have a small breakfast or no breakfast, you will spend all day hungry. This will cause you to tend to eat snacks, and, unless you are very organized (e.g. carry fruit and vegetables in a lunch box), snacks (e.g. chocolate bars) tend to be high in fat. It's much better to load up with quality food at the start of the day so that your starting condition is unhungry. In particular, if you skip breakfast and have a small lunch, by the time you get home, you will be ravenous and will be more likely to gorge yourself within the 20 minute time window described in the "Eat slowly" section below. It's best to choose a form of breakfast that provides you with a slow-release carbohydrate burn that will sustain you throughout the day. One of the best breakfasts you can have is oats/porridge which provide slow-release energy throughout the day and lots of fibre. It also makes you feel full. If you add a sliced banana and some honey, it's a great breakfast. Just don't have it so often that you get sick of it. Mix it in with low-sugar, high-fibre cereal breakfasts.

Eat five times a day: This does not mean have five full meals a day. It just means that you should split some food off from each meal and have it between meals. For example, instead of eating an apple at the end of your lunch, have it at 4pm. The experts seem to agree that the body maintains a more even blood sugar level and can manage its energy better (and will tend to burn more energy) if the energy is delivered in many small meals rather than two or three big ones. I'm not sure how this fits in with the advice to have a large breakfast. I suspect that breakfast is the exception because it "primes" the body in the morning and convinces it there's no famine ("break fast"!). I don't take this advice (yet) because I'm a little concerned about extra acid attacks on my stomach and teeth, and I usually feel too busy to be bothered snacking between meals anyway. However, the experts seem to agree that five meals a day (e.g. three meals and two healthy snacks) is a good thing.

Eat slowly: The body's "hunger" signal takes about 20 minutes to turn off after sufficient food has entered the stomach. This means that if you are feeling hungry, there is a 20 minute window in which you can overeat and still not feel full. The worst case is probably when you approach a smorgasboard ravenous! Eating slowly provides the body time to turn off the hunger signal before too much food is consumed.

Research and set a target weight: Consult your doctor and find out what your optimal weight is. This will provide you with the conviction that heading towards that weight is a "good thing" rather than becoming concerned about becoming underweight. There is a scale called the Body Mass Index (BMI) scale which relates height to optimal weight. This can be helpful, but it is best to consult a doctor as the optimal weight also varies with body shape types.

Weigh yourself regularly: "What gets measured, gets done!". If you want to lose weight, getting into the habit of weighing yourself once a week or day will provide feedback on whether what you are doing is working. Expect your weight to vary, with each reading, by about one kilogram on either side of your "real" weight. This is due to liquid and faeces retention. Warning: There may be a very serious danger of anorexia that can arise from regular weighing. Anorexics get hooked on their ability to control and reduce their weight. Scales are part of the feedback loop that supports this process. So if you decide to weigh yourself regularly, first pick a target weight and write it down next to the scales, and when you get there, stop!

IMPORTANT: I am not a diet and fitness specialist. The above is just the common themes that have emerged from my reading on the subject. Please do not regard them as prescriptive, but rather as a pool of ideas to mix into your lifestyle in association with professional diet, fitness and medical advice. To the extent permitted by law, all liability is excluded, including contractual, tort and other forms.

Note: Weight has never been an issue to me and I have hardly ever in my whole life been overweight or underweight. However, in early 2000, during a regular checkup, my doctor noted that I was just over the top of the BMI "normal" range and that I should lose a little weight. So I decided to do a bit of research on the topic. This page is the result.

Note: If you are qualified in fitness or medicine and are certain that the above advice contains an error, I would be most grateful if you would email me to correct it. There's enough nonsense out there without me adding more! Thanks.

Ross Williams (ross@ross.net)
10 February 2002