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About Carbohydrates

About Carbohydrates

What are carbohydrates?

Carbohydrates are one of the energy sources your body uses. Carbohydrates are digested in the mouth, stomach and small intestine and converted into chains of glucose called glycogen to be stored in the liver and muscles. Glycogen is used by the brain and also by your muscles when you exercise or do intense physical activities. Carbohydrates can also have a muscle sparing effect. If you are on a low carbohydrate diet,  your body will turn amino acids into glycogen and if there isn’t enough carbohydrates or protein it can even breakdown muscle tissue to do so, not what you want.

Us humans unfortunately have developed a craving for carbohydrates, especially the sweet type. This is due to the fact that in the past there wasn’t a lot of it around and the body knew that is was a high energy food ideal for our more physical/labour intensive type of life style in the past, however in modern times with our less active lifestyle, plus the ease in which we can now get hold of any type of food, has lead to an increase in overweight people and type2 diabetes.

Types of carbohydrates

Although all carbohydrates end up as glucose, there are several types, which your body utilises, digests and stores in different ways. There are simple carbohydrates and complex carbohydrates, which incorporates starchy and fibrous carbohydrates.

Simple carbohydrates

These consist of a single sugar molecule (monosaccharide) or  two single sugar molecules linked together (disaccharide). They are mainly found in foods as fructose (fruit sugar), lactose (milk sugar), and sucrose (table sugar)

Simple natural sugars from fruit and milk are ok in small amounts, but sucrose and high fructose corn syrup (which are actually a combination of fructose and glucose) isn’t and these should be eliminated as much as possible (see about insulin here).


This is mainly found in fruit, honey and vegetables, but it is also found as an added sweetener to many foods as high fructose corn syrup (a combination of fructose and glucose) and this added type of fructose sugar can be a problem if eaten in large quantities. Fructose is only metabolised by the liver, consuming too much of the added sugar can lead to numerous issues, including the liver converting excess fructose to fat. However that shouldn’t stop you eating whole fruit and vegetables, which is full of vitamins, antioxidants, fibre and more likely to fill you up and doesn’t have high concentrations of fructose, unlike fruit juices which makes it too easy to drink large amounts of fructose. I recommend 1-2 pieces of whole fruit per day and no specific limit on vegetables (more on that in the following articles).


This is a natural simple sugar found in milk and for some it can be a problem. Many people are lactose intolerant  and unable to digest it and therefore will suffer from bloating, gas and possibly stomach aches and diarrhea from dairy products. I personally keep my dairy intake quite low, but don’t eliminate it completely, as  they do provide good protein, calcium, Vitamin D, numerous B Vitamins and several minerals.


Also known as table sugar and refined sugar, it is similar to high fructose corn syrup and also made up of fructose and glucose and can come from plants or be man made in the lab. Sucrose is often added to a lot of packaged and processed foods and drinks as a sweetener and also too often added manually to foods and drinks by those with a sweet tooth. This stuff has next to no nutritional value and should be excluded from your diet.

Reducing sugar in your diet

One thing I will like to add here, is eliminating or reducing sugar can lead to withdrawal symptoms for many people, such as headaches and bad mood. For the brain, sugar can be quite addictive or even pleasurable, hence the cravings we get. However if you can stick to your reduction or total elimination of sugar, then within a couple of days or a week or two, you should start feeling less of these symptoms.

Complex carbohydrates

Also known as polysaccharides because the sugar molecules are linked together in long complex chains. Complex carbohydrates can help slow down food absorption and stabilise insulin.

Starchy carbohydrates

These are normally easily digested. Unrefined starchy carbohydrates include whole grain foods, brown rice, barley, potatoes, oats, popcorn, vegetables and beans, which generally have a higher fibre content. However some starchy carbohydrates are refined by the food manufacturers, which removes much of the fibre from them, turning them into more of a simple carbohydrate. These more refined starchy carbohydrates include white flour, white bread, cereals, pasta and noodles, white rice and refined wheat, so limit or avoid these.

Fibrous carbohydrates

These are not digested by us humans and mainly come from vegetables, legumes, fruits and whole grains. They have a low calorie density, slows down gastric emptying and help fill you up without the unnecessary calorie intake, but also help promote healthy digestion, are great colon cleansers and also protect against gastrointestinal diseases.

Dietary Carbohydrates

Very low carbohydrate diets have been made popular because of its effect on body fat utilisation, as by depleting your glycogen stores forces your body to burn more fat for energy and while this certainly works and may seem like a good idea, it very often will backfire on a long term basis, as I have stated before while going ketonic may be good for fat loss, it isn’t something you can do for long and to make matters worse, when you return to a more normal eating habit, you will likely gain much if not all of your weight loss and often more. You need a sustainable nutrition plan for long term health, not quick temporary fixes. Also as stated in previously, carbohydrates are converted into glycogen and for every gram of glycogen there is 2.7 grams of water and as such carbohydrates also hydrate your muscles, therefore what looks like fat lose can quite easily be water, creating the loss of weight and size. This lack of carbohydrates can lead to fatigue, weakness, headaches, kidney issues and much more.

I’d like to add a caveat here: Those that are classed as obese or who have type-2 diabetes may require a reasonable low carb diet to ensure they get a good start in reducing their body fat and for some it can work very well to subdue their diabetes.

So very low carbohydrate diets are not my recommendation, what about consuming too much carbohydrates then? If you consume too much for your current energy expenditure it is either stored in your muscles and liver first if they are not already fully topped up with glycogen and then after that it will start to slow down the burning of fat and then also convert it to triglycerides and added to your fat stores. In order to know how much to consume you must try to get an idea of how much your body uses for its daily activities, following a plan will help you do this. Did you know that most of your day to day sitting, reading, watching TV etc will burn both carbohydrates and fat, and in fact when you are rested you are actually burning more fat than carbohydrates, however the problem is fat has nine calories per gram and it takes a lot of time doing nothing to shift a bit of fat.

One great way to burn more fat cells is to exercise, with a gradual change to more fat cells use than carbohydrates. Check out the Exercise and workout section where I explain weight training, body weight training and HIIT.

How does certain types of carbohydrates effect its use and the body?

Glycemic index (GI index)

The Glycemic index (glycemic load per gram of carbohydrate) is a measure of how carbohydrates affect blood glucose concentrations and the score assigned to it tells you how fast a food can be converted to sugar by the body.  As expected, glucose itself has a high value because it is rapidly absorbed into the blood stream, its GI or glycemic load per gram has a score of 100. Generally speaking food with a score lower than 55 are regarded as best and you want to try to stick to lower glycemic foods. You can however slow down higher glycemic foods by combining fats and protein with them, as they will slow down its ingestion, making it more stable.

Foods that have a score higher than 70 really should be either eliminated or reduced way down. White flour is one of those that should be eliminated, as it is processed in the body just like simple sugars, so try to avoid anything made from this. Sugar is bad for you because it increases bad cholesterol, causes hypoglycaemia, reduces growth hormone, supplies excess calories (they are calorie dense, due to the lack of fibre that complex carbohydrates have), cause diabetes and make you insulin resistant, stopping glucose from being able to enter your muscles, fat cells and liver. To ensure you know what’s going in your mouth read labels carefully or better still keep away from ready-made meals and most man-made produce, which are full of these empty calories.

My recommendation is to eat good quality low glycemic carbohydrates spread evenly throughout the day. Get a good mix of starchy carbs and fibrous carbs. If you are not active or overweight, get more fibrous carbs as these are harder for your body to digest and store. I would say most people need to take in roughly around 35-50% of their calories from carbohydrates, although calorie counting isn’t important, this is just a very rough idea of the percentage of this macro against your total nutrition plan.

For your information: There are 4 calories per gram of carbohydrates.

Good sources of starchy Complex Carbohydrates

  • Oatmeal
  • Cream of Rice
  • Cream of Wheat
  • Cream of Rye
  • Oat bran
  • Quinoa
  • Barley
  • Buckwheat
  • Popcorn – plain
  • Yams/sweet potatoes, carrots
  • Legumes/beans/lentils
  • Brown Rice
  • 100% whole grain cereals, pasta, bread, crackers
  • (see below for refined starchy foods to avoid).

Good sources of Complex Carbohydrates: (Fibrous)

  • Asparagus
  • Artichokes
  • Eggplant
  • Wheat Bran
  • Broccoli
  • Okra
  • Cauliflower
  • Green Beans
  • Brussel Sprouts
  • Peas
  • Cucumber
  • Squash
  • Collard greens
  • Mushrooms
  • Zucchini
  • Lettuce
  • Pepper, green or red
  • Tomatoes
  • Spinach
  • Kale

Good sources of Natural Simple Carbohydrates (Fruit)

Watch portion sizes and note that some have more sugar than others – 2-3 pieces a day is fine. The more fat you want to lose eat 1 maybe 2 pieces and if you are lean go for 2-3 pieces of fruit per day.

  • Apples
  • Blueberries
  • Bananas
  • Oranges
  • Raspberries
  • Berries
  • Nectarines
  • Plums
  • Grapes
  • Peaches
  • Cantaloupe
  • Grapefruit
  • Pears

Try to eat fruits with other fats and protein foods to slow the absorption of the sugars in them down.

Carbohydrate foods to avoid

  • Salty and sugary cereals
  • Refined starchy foods: White rice, flour, bread, potatoes, noodle, refined grains
  • Large fruit salads (easy to get carried away)
  • Fruit juice (too sugar dense)
  • Soda/fizzy drinks
  • Canned/processed fruit
  • Sweets/cakes/biscuits etc
  • Dried fruit (too sugar dense)
  • Flavoured yogurts
  • Vegetable juices
  • Hell anything that isn’t a single food product and doesn’t have a bunch of added crap in it.


Remember all carbohydrates get converted to glucose and if not used by the body will increased your body’s fat stores. Try to eat a good mix of complex carbohydrates and a helping or two of fruit each day.

Return to the nutrition plan main page.
Please also see About resistant starch