Why sugar makes you fat

Sugar, Insulin and fat storage

For a flat tummy, we need to eliminate, as much as possible, sugars and starch. Not fat. When we eat something with a high GI (glycaemic index) it is very rapidly digested by the small intestine and released into the bloodstream as blood glucose, or BGL. This is sometimes also called blood sugar.

The glycaemic index, by the way, is a measure of how quickly foods are turned into blood glucose by our digestive system. It roughly equates to the amount of sugar in a food or drink. So glucose has a GI of 100 while broccoli has a GI of only 15.

Now, here’s the science. When we have something with a high GI, blood sugars rise quickly. Constantly high BGLs are bad for us, so we release a hormone (insulin) that tells the cells what to do with all that sugar. The cells open up (sort of) and, like a little fork lift truck, take the energy away for storage in the liver, muscles, and fat stores. This reaction is so reliable that a scientist in the 1930s (Willian Falta) discovered that in cattle it was impossible to fatten animals with insulin deficiency. So,  when insulin is present you are storing fat.

Breaking the fat burning process

But it gets worse. Under normal conditions, we metabolise fats and blood sugars in the presence of oxygen to make energy. The oxygen is where the name “aerobic” comes from. We use this aerobic energy up to 60% of maximum heart rate or 60% of effort; so most of the time. Thus most of the time we are burning fat. HOWEVER, when insulin is present, it interrupts this chain. We stop burning fat.

Logically this makes sense; blood sugar levels are already high when insulin is present. So there is no point us metabolising fat and releasing it into the blood as BG (blood glucose). If we did it would be like putting petrol into a car that is already full.

So when we eat/drink something with a high GI it’s a double blow – we store fat but stop using the stores we have. This is why, in many cases, people may be exercising and eating perceived healthy foods, but not quite getting a flat tummy.

So the key to fat reduction (not just weight loss),  is the elimination or reduction of

a) sugar

b) starch

This is best done in 5 steps.

1. Remove the easy sugars from your diet

Don’t cry, but this means all sweets, cakes, biscuits, chocolate, fizzy drinks (except low calorie ones), fruit juices, cereal bars, most breakfast cereals and fruit yogurts, as well as sweet spreads like jam and honey, and all dried fruit. Drying fruit simply compacts its sugar into a smaller package.

Don’t view this as deprivation: look at it instead as breaking an addiction. You may suffer withdrawal symptoms for a few days to a few weeks, but substitute sweet snacks for savoury ones (see 5, below), switch to diet drinks and persevere. Eventually you will break the chain and be free.

Once this tricky bit is over, you will stop craving sugars and feel healthier, slimmer and more in control of your eating.

2. Remove the hidden sugar

Look at the label on everything: you’ll be surprised how sugary many foods are, from salad dressings and mayonnaise (especially the low-fat versions which have more sugar to compensate for the lack of fat) to balsamic vinegar and condiments such as  salad cream, barbecue sauce,  ketchup and hoisin sauce.

Any ready meal, pizza or packet of sausages with more than 3% sugar is also a no-no. Once you’ve followed steps 1 and 2, you will have eliminated most of the fructose you encounter in a day; it’s this fructose that is the most addictive. You’re now aiming to get to a maximum of five teaspoons of sugar a day, all in. That’s 20g.

3. Replace the sugar – with care

Those foods lowest in sugar tend to be strategically hidden at the end of the aisle in supermarkets, so start “patrolling the perimeter” for untampered meat, dairy, veg, fruit beans and pulses.

You will have to cook more meals from scratch, although you can still buy ready-packaged food – just make sure you examine the label.

If it contains more than 3g of sugar per 100g, step away. If it’s a liquid, don’t touch it if it contains any sugar at all.

Always avoid low-fat options and anything advertised as “light/lite” or “healthy options (manufacturers will have taken out the fat but added sugar to improve the taste). Some ready meals are ok, but again, read the label. M&S fuller longer are generally ok for example.

When buying fruit, go for lower-sugar but higher fibre ones: berries and kiwis are better than bananas, grapes and and oranges. Fruit juice is a big no-no. It’s all the sugar but none of the fibre.

4. Change your habits

If some routines in your life are linked to eating sugar, you may have to give them up for a while. This could be having a project go well or having a great/awful meeting. Similarly, if watching TV in the evening goes hand in hand with snacking, find another way to relax for a while: read a book, use the computer or go for a walk.

5. Come up with tasty alternatives to a sweet fix

Identify danger times and situations: when are you most tempted to snack on sugary foods? Note them all down, be honest with yourself, and think up an alternative.

If you usually have a biscuit when making a cup of coffee, move the biscuits (throw them out) and keep a jar of nuts by the kettle instead (yes, they are calorific, but not sugary).

If you get hunger cravings in the evening, drink a glass of milk and have some cheese – or some crisps if you must have a treat. The former are calorific, but will not provoke an insulin reaction.

Substitute wine and beer for low calorie mixers with a spirit and swap your mid-morning muffin for some nutty, seedy toast.