The Woes of Weighing

Health and fitness expert Andrew Cate explains why your bathroom scales alone are no measure of diet success.

Your bathroom scales might be a quick, easy measure of diet progress, watching those numbers reduce, but that's not necessarily a measure of success. Here are 10 reasons why.

1. Body fat

Your bathroom scales don't actually tell you what you really need to know.

2. A poor measure

When you begin to change your lifestyle, it's normal to want reassurance that this change from your comfortable, sometimes lazy lifestyle is worth it. People focus on results, and weigh themselves regularly. But when you first start to exercise, it's normal to gain one or two kilograms of muscle. You might even gain a little more if you are just starting resistance (weights) training. 

3. Muscle loss

Muscle weighs more than fat because it is dense tissue and holds water. So if you are on a strict diet or cut out carbohydrates, forcing your body to break down muscle tissue, it will look good on the scales but be detrimental.

4. Weight gain can be healthy

Jumping on the scales and finding you've gained weight would normally ruin your day. But if you are exercising more and eating well, you'll gain weight in the form of fluid and muscle and lose body fat. But if you lose fat and gain muscle at the same rate, you may gain a kilo or two, because muscle is heavier. The more active you are, especially if you do resistance training, the less accurate scales reflect your fat loss. Gaining muscle doesn't make you bigger, just firmer, stronger and fitter.

5. Water loss

Fluctuating fluid levels cause weight variations. This is more pronounced in women, whose fluid levels change throughout the menstrual cycle. The body is approximately 60 per cent water, a significant proportion of your total body weight. Fluctuating fluids can cause your weight to rise and fall by up to three kilos in a day, so excessive sweating and partial dehydration will show as a weight loss on the scales. Eat or drink and all that weight comes back!

6. Bone-density change

Strict dieting can lead to calcium deficiency, which can increase your risk of osteoporosis. In women, strict dieting can reduce estrogen production and lead to osteoporosis. Your bones become weaker—more brittle and less dense. On the other hand, exercise actually increases your bone density.

7. Poor predisposition

If you lose weight through dehydration and muscle loss, your metabolic rate slows and your capacity to burn kilojoules reduces. When you go off a crazy diet, you have less muscle and a slower metabolism, so the weight returns quite quickly. This makes it even harder to lose body fat in the future.

8. Fats—and fat

Excess fat stored around your tummy is more dangerous to your health than fat stored elsewhere, such as thighs. It's a strong indicator of your chances of developing heart disease and lifestyle illnesses.

9. Effect of ageing

One argument people use to keep their scales is that they want to get back to a weight they once were happy with. But you lose muscle and bone density as you age, so you can't compare the past with the present—or make it a realistic goal.

Ironically, the best way to prevent the loss of muscle and bone density is resistance training, which will increase your weight on the scales.

10. Fitness, the best measure

Imagine if you have exercised four times a week for eight weeks, then you go and weigh yourself and your weight hasn't changed one bit. Is it worth it? The scales say you've achieved nothing, but you may well have lost centimetres off your girth, reduced your body fat and increased your lean muscle mass and improved your fitness. So you will probably feel better and breathe more easily during exercise. Of course it's worth it! The most effective methods of weight loss—nutrient-depleting diets, fasting, not drinking enough water, cutting carbs, sickness—will make you feel tired and even miserable. One of my clients put it this way: “I had the flu badly, but at least I lost three kilos.” That's a path I don't recommend.