What are carbohydrates and are they making us fat?

Carbohydrates are molecules containing carbon, hydrogen and oxygen. They supply us with the fuel-energy that enables us to function.  Proteins and fats are other energy sources. Carbohydrates consumed in excess of our energy needs, are quickly transformed into stored fat within our bodies.

For years there has been debates concerning the optimum diet to achieve weight loss including “low fat high carb diets” and “low carb high fat diets”.

Increasingly there is growing evidence to support that “low carb high protein diets” are more effective than “low fat high carb diets” in the management and control of our weight and stored body fat.

Our Government Health Authorities and many main stream nutritionists are conservative and resistant to change their views in the face of the growing scientific evidence against the previously perceived wisdom to reduce fats and exercise strict calorific control.

Contrary, we need to stop counting calories and eat until we are full. We need to count our carbs and in particular the bad processed carbs, from Ronald Mac etc.. It has been proven many times that by restricting carb intake, not calorie intake, we will lose weight.

The key concern it seems for many of main stream nutritionists is that a “low carb high fat diet” will cause heart disease. However, increasingly the scientific evidence is showing this may be fallacy not based on real scientific evidence and not all fat is bad. The real culprit causing obesity and heart disease is added sugar in our diet and which is pervasive in so many of our processed foods including low fat foods.   

Kris Gunnars, of authoritynutrition.com has undertaken a review of 23 respected gold standard scientific studies which compare “low fat” and “low carb” diets. The chart below is a summary of the results and shows that “low carb” resulted in greater weight loss. 

So what are carbohydrates in terms of food and do we need them?

Carbs consist of three different groups:-

Starches, which are found in vegetables and grains and are referred to as “complex carbohydrates”. Complex carbs provide the body energy more immediately than consumed fats and protein and are a key fuel for the brain and nervous system.  Complex carbs or starches, unlike sugars are released into the blood stream slowly and so you will not crash and crave bad carbs later in the day.

Sugar on the other hand is a simple carbohydrate and it is released very quickly into the blood stream giving an energy boost. Sugars are naturally occurring in the fruit we eat. They are also added into the numerous processed foods (toxins) that we consume. Added sugar is the major cause of obesity, metabolic syndrome and type 2 diabetes.

Fibre is only found in whole fruit (not in juice), vegetables and whole grains. It promotes a healthy digestive system and is key to preventing gut cancers. There are two types of fibre insoluble and soluble. Soluble fibre reduces the amount of bad cholesterol (LDL) within the blood stream. Porridge in particular contains soluble fibre which soaks up bad cholesterol. Insoluble fibre is not digested but helps your digestive system to move and remain healthy.

Another benefit of eating sufficient fibre, is that it makes us feel fuller longer without being hungry.

Carbohydrates (apart from sugar) provide significant benefits to our health and well-being. So what is the problem?  The first is consumption of too much sugar and in particular added sugar and then refined grains where the fibre and other nutrients have been stripped out. Carbs are good but in moderation and only the complex ones.

How many carbs should we eat?
 

Let us, look at the National Health Service (NHS) in UK "Eat Well Plate" and calculate the amounts of the different types of food it may represent.

 

It is split into 5 segment food groups as follows:

• bread, rice, potatoes, pasta and other starchy foods - 33%
• fruit and vegetables - 33%
• milk and dairy foods - 15%
• meat, fish, eggs, beans and other non-dairy sources of protein - 12%
• foods and drinks high in fat and/or sugar - 8%

 

Typical Foods and Quantities to Follow NHS Eat Well Plate Guidelines  

Observations

In carbs category the energy density varies quite a lot. In aiming for weight loss it may be better to target foods with lower energy density. In this way you will feel fuller by eating a greater volume of food with less calories by weight. Rice and potatoes are better choice than bread and pasta.

If you only ate spinach you would need to eat 3kg to reach the recommended calorific guidelines. This is not realistic: unless you are a gigantic rabbit.

We need a paradigm shift in considering how much vegetables we consume and to increase them substantially. By blending whole vegetables you can increase the quantities of vegetables you consume. 

The quantity of sugar in fruit are high.  If you are aiming for weight loss it is better to increase your green vegetable intake more than your fruit intake. Personally I am careful of fruit sugar (fructose) and 3 pieces of fruit a day is plenty.

Summary of carbohydrate intake by following Eat Well Plate

  









So how much carbohydrate should we eat for weight loss and would the NHS “Eat Well Plate Guidelines” allow us to achieve weight loss?

We can discount fibre as that is mainly passing through and only count the starches and sugar and the total amount of carbs by following the NHS “Eat Well Plate Guideline” is 300g.

This amount of carbs is far in excess of what will allow us to lose weight without restricting calories in other foods and so feeling hungry.

The answer to how many carbs we should eat to lose weight varies from person to person, but the range is much lower than 300g. To lose weight you need chose one.

Greater than 150g carb (half NHS amount). You need be on calorie restriction plus exercises to lose weight. You may feel hungry.

Equal or less than 150g carb intake per day. You need to exercise to lose weight, but can eat more protein and fats. This may be the maintenance range once you have lost weight.

50g to 100g carb. If you increase protein and fat intake you will not feel hungry. Also by eating only complex carbs, such as starch you will have immediate energy. Porridge Oats are recommended. By staying in this range for carbs you will lose weight easily and by eating protein and healthy fats until you feel full and not go hungry. You should undertake light aerobic and some resistance exercise to maintain muscle mass.

50g or less, this is “Atkins” territory. It is effective for fat loss but not sustainable for most people overtime. Plus you will smell of bad decay.   

The gram amounts above only include starch and sugar. Fibre and "resistant starches" may be disregarded in counting carbs. 

When undertaking weight reduction it is key to do it at a sustainable pace and also undertake strength/resistance training to maintain muscle mass. Regular aerobic exercise also reduces blood sugar, helps reverse metabolic syndrome and allows the body to burn fat stores.