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7 Healthy Carbohydrates That You Should Be Eating Regularly

 

June 13, 2009 By Tom 10 Comments

In my last few articles I have been discussing carbohydrates in detail.  I have covered the benefits of consuming the right amount, the disadvantages of consuming too many and the methods to follow when choosing carbohydrates.  Today I want to make this advice a little more practical and supply you with seven healthy carbohydrates that you should be eating on a regular basis.

1) APPLES:- Apples are tasty and come in a variety of flavours.  They are also small and portable meaning that they can be eaten any time and anywhere.  On top of this apples are rich in a number of healthy nutrients including fibre, vitamin C, various antioxidants, flavonoids and phytonutrients.

Fibre has a number of health benefits which include improved blood sugar control and improved bowel health.  Vitamin C also performs a number of important functions including helping your wounds heal and strengthening your immune system.  Antioxidants, flavonoids and phytonutrients all act in a protective capacity with antioxidants protecting the body from oxygen related damage, flavonoids triggering the production of natural enzymes that fight disease and phytonutrients themselves having disease preventing qualities.

2) BANANAS:- Bananas are another fruit that is small and easy to carry making them perfect for snacking.  I find that they are particularly good as a pre-gym snack as they give you energy for the workout and eliminate any hunger pangs that may occur as you exercise.  Bananas are also nutrient rich containing high levels of fibre, manganese, potassium, vitamin B6 and vitamin C.

Manganese has various health benefits which include helping your body to absorb various vitamins and keeping your bones strong.  Potassium also helps your body in various ways which include lowering your blood pressure and promoting bone thickness.  Vitamin B6 helps your body break down protein into a form that your body can use and also assists with hormone regulation.

3) BELL PEPPERS:- Bell peppers can be eaten raw or cooked as part of a meal or on their own.  I like to put them in curries, casseroles, fajitas and more as they add a perfect blend of colour and flavour to the meal.  Bell peppers also contain high levels of fibre, vitamin B6, vitamin C, vitamin E and vitamin K.

Vitamin E is a powerful antioxidant that protects your cells from the damage that using oxygen can cause.  It can also protect you from cancer, diabetes and heart disease.  Vitamin K helps your blood clot and is therefore essential for proper wound healing.  Without adequate levels of this vitamin your blood will not clot and even the smallest wounds will bleed continuously.

4) MUSHROOMS:- Mushrooms are extremely versatile and can be added to casseroles, curries, stews and more.  In fact I have them with almost all of my evening meals.  As well as being a tasty addition to most meals, mushrooms are also one of the most nutrient rich food choices around.  They contain extremely high levels of the B complex vitamins (particularly vitamin B2), copper, selenium and tryptophan.

The B complex vitamins are all vital for getting energy and nutrients from the food you eat whilst vitamin B2 also promotes healthy skin and vision.  Copper performs a number of important functions which include keeping your connective tissue healthy and helping your body absorb iron.  Selenium is a powerful antioxidant which protects your cells from oxygen related damage.  Tryptophan is a nutrient that assists with relaxation and can both help you sleep and improve your mood.

5) ONIONS:- Onions are another versatile food that can be put into almost any meal.  Although not everyone is a huge fan of the taste I think that onions add a perfect crunchy texture to meals.  They also provide your body with various nutrients including chromium, fibre, manganese, molybdenum, vitamin C and various flavonoids.

Chromium improves your cells responsiveness to insulin, vitamin C and certain flavonoids  which allows them to absorb blood glucose and other nutrients more easily.  The flavonoids in onions have also been linked with the prevention of a number of cancers including breast cancer, colon cancer, ovarian cancer and prostate cancer.

6) ORANGES:- Oranges have a nice, sweet but tangy flavour.  Like the other fruits listed, oranges are very portable making them a perfect snack food.   They are most famous for their high levels of vitamin C but this is not their only nutritional benefit.  Oranges also contain high levels of fibre, vitamin A , vitamin B1 and vitamin B9.

Vitamin A is essential for healthy vision and a deficiency can lead to the onset of night blindness (a condition that makes it almost impossible to see in low light levels).  Vitamin B1 and vitamin B9 are both needed by your body to properly break down food into energy.  However, vitamin B1 also helps keep your nervous system healthy whilst vitamin B9 also assists with the production of serotonin which can boost your mood.

7) SPINACH:- Spinach is another surprisingly versatile carbohydrate source.  Canned spinach is a great, tasty addition to beef and lamb based dishes whilst fresh spinach goes great on sandwiches.  On top of this it is full of nutrients including calcium, iron, magnesium, vitamin A and vitamin K.

Calcium and magnesium are both very important nutrients which helps you build strong, healthy bones.  They also support healthy muscles and nerves.  On top of this calcium helps your blood clot whilst magnesium promotes good blood circulation.  Iron helps your body produce energy and also supports a healthy immune system.

As you can see there are many fruits and vegetables out there which make excellent carbohydrate choices and you really should consider adding some of these to your diet.  The seven I have listed are all foods that I eat on a regular basis but there are a lot more healthy carbohydrate choices out there.  If none of the above take your fancy then do a little research and find some healthy carbs that you do like.  Not only will this provide your body with its preferred energy source but it will also supply you with many vital nutrients.

Now I want to hear your thoughts.  Do you eat any of the above carbohydrate sources on a regular basis?  Are there any other foods that you would recommend adding to this list?  Let me know by posting a comment.

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The Disadvantages of Consuming Too Many Carbohydrates

 

June 10, 2009 By Tom 14 Comments

My recent series of articles have focussed on carbohydrates.  Over the course of these articles I have come to the conclusion that carbohydrates have a number of benefits as long as you choose wisely.  However, even if you do choose the right carbohydrates you can still overindulge.  Today I am going to be discussing some of the potential drawbacks associated with consuming too many carbohydrates.

1) WEIGHT GAIN:- Carbohydrates are your body’s preferred energy source.  When you eat any type of carbohydrates your body breaks them down into glucose in the digestive tract.  This glucose is then released into the bloodstream causing your blood glucose levels to rise.  Your pancreas responds to these high blood glucose levels by releasing insulin (a hormone that allows your body’s cells to take glucose from the blood and use it for energy, store it as glycogen or store it as fat).  Once your blood glucose levels have become sufficiently low your pancreas stops releasing insulin and starts to release glucagon (a hormone that helps your liver convert stored glycogen into glucose and release it into the bloodstream).

If you eat a moderate amount of carbohydrates your body’s cells will be able to use what they need for energy and store any excess as glycogen.  However, these glycogen stores are limited and once they become full any excess glucose is stored as fat.  Therefore, by eating too many carbohydrates your body is forced to store fat.  Furthermore, eating too many carbohydrates over a long period of time means that these glycogen stores never become depleted so fat storage continues to increase and you continue to gain weight.

2) INCREASED TYPE 2 DIABETES RISK:- Type 2 diabetes develops when either your body’s cells start to resist insulin or your pancreas fails to produce enough insulin.  Although no one knows exactly what causes diabetes there are a number of risk factors which can be linked back to high carbohydrate consumption.

First, (as I highlighted above) eating too many carbohydrates leads to increased fat storage.  Fat cells have fewer insulin receptors than muscle so the more you have the less responsive your body is to insulin.  Secondly, eating too many carbohydrates causes your blood glucose levels to rise meaning that insulin has to be released.  If you continue to eat excessive amounts of carbohydrates your pancreas has to produce and release increasing amounts of insulin to cope with your increasingly high blood glucose levels.  Pushing your pancreas to the limit like this can ultimately interfere with its ability to produce insulin.

Both insulin resistance and your pancreas failing to produce enough insulin are characteristics of type 2 diabetes.  Therefore, long term over consumption of carbohydrates can increase your risk of contracting this disease.

3) POOR APPETITE CONTROL:- As I mentioned above eating carbohydrates causes your blood sugar levels to rise.  Although the rate at which they rise is partially influenced by the type of carbohydrate you eat, eating too many in one sitting will cause a large increase in blood glucose levels.  This then causes your pancreas to release a large amount of insulin in response which leads to an equally large decrease in blood glucose levels.  When your blood glucose levels fall your brain sends out hunger signals meaning that you crave even more carbohydrates a short time after eating them.  The overall result is poor appetite control as you are constantly craving carbohydrates despite eating large, regular amounts.

4) FLUCTUATING ENERGY LEVELS:- As I discussed above eating excess carbohydrates causes a rapid surge and then a rapid fall in blood glucose levels.  This has a direct effect on your overall energy levels meaning that you will suddenly feel full of energy and then shortly after your energy levels will crash.  Fluctuating energy levels makes it very difficult to function properly throughout the day as you will be constantly switching between feelings of too much energy and not enough energy.

5) PERMANENT DAMAGE:- In my article on the damage caused by diabetes I highlighted that high blood glucose levels can cause permanent damage to your body.  Eating too many carbohydrates can contribute to high glucose levels and therefore contribute to this damage.  The actual damage can affect all your major organs and vessels including; your heart, your kidneys, your eyes, your nerves and your blood vessels.

Carbohydrates are often given a bad reputation for all the reasons listed in this article.  However, the truth is that all the above are not a result of carbohydrates being bad – they are a result of consuming too many carbohydrates.  If you control the amount of carbohydrates you are eating you can avoid these health complications whilst providing your body with the energy and nutrients it requires.

Now I want to hear your thoughts.  Have I missed any disadvantages?  Do you agree that overconsumption of carbohydrates is the key problem?  Leave a comment and let me know.

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The Benefits of Carbohydrates

 

June 7, 2009 By Tom 14 Comments

In my last few articles I have been focussing on carbohydrates.  I started by explaining exactly what they are and then covered a number of related topics including the glycemic index and the steps you should take when choosing your carbohydrates.  In this article I am going to cover the benefits that carbohydrates can provide.

1) THEY ARE AN EXCELLENT ENERGY SOURCE:- The primary function of carbohydrates is to provide your body with energy.  When you ingest any form of carbohydrate (whether it be pure sugar, whole grain bread or a piece of fruit) it is broken down into glucose in the digestive tract.  This glucose is then released into the bloodstream where your cells can use it for energy.

Your body can convert fats and proteins into energy through a process called gluconeogenesis.  However, this process is very inefficient and prevents fats and proteins from performing their primary functions which are to build, protect and repair your body’s cells.  Therefore, one big benefit of carbohydrates is that they provide your body with an easily accessible energy source.

2) THEY ARE A RICH SOURCE OF FIBRE:- If you choose your carbohydrates wisely then you should be getting the majority from fruits and vegetables.  Both of these plant based foods are an excellent source of insoluble and soluble fibre which have a number of health benefits.

Insoluble fibre is a type of fibre that absorbs water in your digestive tract and helps push waste materials through.  Its benefits include keeping your digestive tract healthy, reduced bowel disease risk and reduced constipation.  Soluble fibre is a type of fibre that dissolves in water in the digestive tract to form a gel like substance which holds foods there for longer.  It helps slow down digestion which keeps your blood sugars stable and allows you to absorb a greater amount of nutrients from your food.

3) THEY ARE A RICH SOURCE OF VITAMINS:- Fruits and vegetables do not just provide you with fibre – they are also an excellent source of vitamins.  Each of the thirteen vitamins are essential for the proper functioning of your body and have a number of benefits.  They protect you from a number of diseases (including cancer and diabetes), boost your immune system, promote proper growth, help your body produce various cells and much more.

4) THEY ARE A RICH SOURCE OF PHYTONUTRIENTS:- Many fruits and vegetables provide your body with phytonutrients too.  These are chemicals that are found naturally in plants and have protective properties.  They can act as antioxidants (which protect your cells from the damage using oxygen can cause), protect your body from harmful bacteria and also protect your body from certain diseases.

Carbohydrates are often seen as the nutrient to avoid when it comes to healthy eating and weight loss.  People seem to forget that they are the best and most efficient way for your body to get energy.  They are also a great source of many healthy nutrients including fibre and vitamins which are often unavailable in other food types.  Without carbohydrates your body will become malnourished and inefficient.  As long as you eat sensible amounts and stick to unprocessed, natural carbohydrates you can give your body the energy and nutrients that it needs and enjoy multiple health benefits.

Now I want to hear from you guys.  Are there any carbohydrate benefits I have missed?  Do you agree with the benefits I have put down?  Let me know by leaving a comment.

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5 Top Tips To Consider When Choosing Carbohydrates

 

June 5, 2009 By Tom 7 Comments

In my last couple of articles I discussed carbohydrates and the glycemic index (GI).  In my article on carbohydrates I discussed the different types and came to the conclusion that you should choose slow digesting, nutritionally dense carbohydrates where possible.  In the following article I looked at the glycemic index as a potential tool for selecting carbohydrates and came to the conclusion that whilst it is a useful starting point, it is flawed and is not something you should fully base your diet around.  In this article I will be bringing this information together and providing you with five top tips to consider when choosing carbohydrates.

1) USE THE GLYCEMIC INDEX AS A STARTING POINT:- The glycemic index gives foods a ranking of between 1 and 100.  It then splits these rankings into three groups; low GI (foods ranked below 55), medium GI (foods ranked between 55 and 70) and high GI (foods ranked above 70).  Low GI foods are seen as the best choice and should be consumed where possible whilst high GI foods should be avoided.  By eating low GI foods you can enjoy a number of benefits which include improved appetite control and protection from type 2 diabetes.

The glycemic index does have a number of problems.  One of these is that a single food can have multiple GIs depending upon how it is cooked, how fresh it is and more.  Another problem is that it is difficult to accurately determine the glycemic index of a meal that contains different types of food.

Despite these problems it is still a good starting point when choosing your carbohydrates.  For example, many fruits and vegetables have a low GI whilst most simple sugars (when eaten in their pure form) have a high GI.  The majority of nutritionists would agree that your diet should contain lots of fruits and vegetables and moderate levels of simple sugars.  Therefore, as long as you are aware of the problems associated with this method and do not rely on the glycemic index fully, it is a good tool to start with.

2) CHOOSE HIGH FIBRE CARBOHYDRATES WHERE POSSIBLE:- There are two types of fibre; Insoluble and Soluble.  Insoluble fibre  absorbs water in the digestive tract and expands into a bulky mass which then continues to move through pushing waste materials as it goes.  Soluble fibre dissolves in water in the digestive tract allowing foods to be held there for longer.

Both types have a number of health benefits.  Insoluble fibre promotes regular bowel movements which helps reduce constipation and lowers your risk of bowel disease.  Soluble fibre slows down the digestive process which promotes better blood glucose control and also allows you to fully absorb all the vitamins and minerals from your food.  On top of this fibre contains zero calories so high fibre foods can help you lose weight because they are naturally lower in calories.

Fruits, vegetables and whole grain products are all rich sources of dietary fibre.  They also contain plenty of vitamins, minerals and other important nutrients making them an excellent carbohydrate choice.

3) CHOOSE VITAMIN RICH CARBOHYDRATES WHERE POSSIBLE:- There are thirteen different vitamins and your body needs each and every one so that it can perform essential functions.  Collectively the thirteen vitamins have numerous health benefits.  They are essential for growth, support healthy vision, keep your bones strong, help protect your cells from damage, reduce your risk for a number of diseases and much more.

Vitamins can be found in a variety of foods.  Cabbage, spinach and other green leafy vegetables are all excellent vegetable sources.  If you want to get your vitamins from fruits then bananas, berries and citrus fruits are all good choices.  Furthermore, all these vitamin rich foods are natural, healthy and full of fibre making them a fantastic carbohydrate choice.

4) CHOOSE NATURAL CARBOHYDRATES WHERE POSSIBLE:- As I discussed in the above two points you should choose fibre and vitamin rich carbohydrates when you can.  Whilst this is generally good advice there are certain highly processed products that artificially add fibre and vitamins back in during processing.  For example, there are a number of soft drinks which contain added vitamins.  Artificially adding these nutrients to processed foods creates two problems.

First, in many cases excessively high levels of these nutrients are added back in.  This can potentially lead to overdosing which has a number of unpleasant side effects.  Too much fibre can lead to wind, constipation and diarrhea whilst overdosing on vitamins can cause pain, cell damage and weaken your bones.

Secondly, synthetic forms of these nutrients are usually not as good as the natural form.  In most cases your body cannot properly absorb synthetic nutrients meaning that they are not as beneficial for you as the natural alternatives.  Furthermore, a lot of synthetic nutrients contain toxic by-products meaning that they can be damaging to your body.

For these reasons you should not just choose fibre and vitamin rich carbohydrates but you should also go natural where possible.  All the fruits and vegetables I have listed so far are fantastic carbohydrate sources that are natural, high in fibre and full of vitamins.  Therefore, you should make the effort to get a selection of them into your diet.

5) KEEP AN EYE ON THE TOTAL CALORIES:- Carbohydrates receive a lot of undeserved bad press.  The truth is they are neither good or bad – they are simply your body’s preferred energy source.  The problem with carbohydrates is that many people consume too many of them without getting adequate amounts of fibre, vitamins and minerals.  This ultimately means that they consume too many calories and do not get enough nutrients from their diet which leads to weight gain and a number of health problems.

Overindulging on any of the three macronutrients (carbohydrates, proteins or fats) is not good for your body.  However, by keeping an eye on the total calories you are consuming and exercising some portion control you can avoid these problems.  As long as you eat sensible portions carbohydrates can be a good source of energy and various nutrients.

For many people choosing the right carbohydrates is a very tough decision as there is so much conflicting information out there.  However, it does not have to be that hard.  Start by choosing a few low GI carbohydrates, make sure that they are natural, high in fibre and vitamin rich and eat a sensible amount.  If you do this then I am sure you will be choosing the best carbohydrates for your body.

What do you guys think?  Is this the right way to choose carbohydrates?  Is there anything vital that I have missed?  Let me know your thoughts by posting a comment.

*****

If you want to learn more about choosing the right carbohydrates I recommend Gilad’s Eat Right Now Nutrition Plan.  As part of this plan Gilad discusses his traffic light method to selecting food which involves labelling all foods; Green (foods that are excellent for you), Yellow (foods that are good for you) and Red (foods that are damaging to your health).  By eating mainly green and yellow foods you can enjoy better blood sugar control, an increased metabolism and much more.


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The Glycemic Index Explained

 

June 1, 2009 By Tom 15 Comments

In my last article I discussed the different types of carbohydrates and the way that your body uses them.  At the end of that article I mentioned that you should choose slow digesting, nutritionally dense carbohydrates where possible.  However, sometimes it can be quite difficult to determine which carbohydrates these are.  That is why today I am going to be writing about one of the methods you can use to choose the best carbohydrates – the glycemic index (GI).

WHAT IS THE GLYCEMIC INDEX?

The glycemic index is a system which ranks foods based on how they affect blood glucose levels.  It is based on research where a selection of healthy individuals were given a variety of carbohydrates to eat.  Their blood glucose levels were then measured every 15 minutes to see how fast and high they increased.  Finally, these changes in blood glucose levels were given a GI of between 1 and 100 with 1 being the lowest, slowest increase and 100 being the highest, fastest increase.  Based on this research the following conclusions were made:
- Low GI Foods = Foods with a GI below 55.
- Medium GI Foods = Foods with a GI between 55 and 70.
- High GI Foods = Foods with a GI above 70.

WHAT IS THE GLYCEMIC INDEX FOR EACH FOOD TYPE?

The glycemic index varies greatly by food type.  I have provided a summary of some of the main food groups below but you can find a full list by clicking here.

BREADS:- The GI of breads varies greatly based on the ingredients used and can range from 42 to 73.  Higher fibre breads generally having a lower ranking.

DAIRY:- Dairy products generally have a low GI because of their high fat content.  For example, milk has an average ranking of 27 whilst yoghurt averages at around 18.

FRUITS:- The GI of fruits is linked to its carbohydrate content with certain fruits being highly concentrated and others being less so.  For example, apples have an average ranking of 38 which is relatively low and reflects their high fibre and water content.  Contrastingly, raisins which are highly concentrated and contain a lot of sugars have an average ranking of 64.

NUTS:- Nuts have a very low GI due to their high fat content.  For example, cashew nuts have an average ranking of 22 and peanuts have an average ranking of 14.

PASTA:- The GI of pasta can range from 26 to 92 depending upon its fibre content, its shape and how quickly it is cooked.  Longer cooking times increase pasta’s GI with harder pasta having a low ranking and softer pasta having a high ranking.

SUGARS:- Sugars normally have a high GI because they are generally digested and absorbed into the bloodstream very quickly.  For example, glucose is ranked 100 whilst sucrose is ranked 68.

VEGETABLES:- Most none starchy vegetables cause little or no increase in blood sugar due to their high fibre and extremely low carbohydrate content.  For example, broccoli has an average ranking of 0.  However, vegetables that are richer in carbohydrates have a much higher GI with potatoes having an average ranking of 80.

WHAT ARE THE BENEFITS OF THE GLYCEMIC INDEX?

The idea behind the glycemic index is that you should choose foods with a low GI where possible.  This helps keep your blood glucose levels stable and reduces large blood glucose surges which have a number of complications including poor appetite control and organ damage.  Eating foods with a low GI is also thought to protect you from type 2 diabetes and heart disease.

WHAT ARE THE PROBLEMS WITH THE GLYCEMIC INDEX?

1) LIMITED SELECTION OF FOODS TESTED:- As I said at the beginning of this article GI values are based on research where healthy individuals were given a selection of carbohydrates to eat and then their blood glucose response was measured.  However, it is not practical to test certain foods and because of this they cannot be given a GI.  According to NutritionData.com only 5% of the foods in their database have GI values.

2) THE GLYCEMIC INDEX CAN BE DIFFERENT FOR THE SAME FOODS:- Certain foods can have multiple GIs with cooking times, the method of preparation, ripeness, individual differences in blood glucose responses and even the research source all having an effect.  For example, unripe bananas have an average ranking of 30 whilst overripe bananas have an average ranking of 52.  Hard pasta which has been cooked quickly has a relatively low GI ranking whilst slower cooked soft pasta has a much higher ranking.  Peaches have a different GI depending upon the research source you choose with one study suggesting an average ranking of 28 and another study suggesting an average ranking of 56.  Furthermore, everyone’s blood glucose response to food is different so a slice of bread may have a different GI for you than it does for other people.

3) THE GLYCEMIC INDEX ASSUMES THAT WE ONLY EAT ONE FOOD AT A TIME:- GI rankings are specific to each food type.  Whilst they can be used when you eat one food individually there is no accurate way to calculate the GI ranking of a meal that contains a combination of foods.  For example, we know potatoes have an average GI ranking of 80 but if we add some cheese (which has a much lower GI because of the high fat content) the ranking of this meal changes.  If we add some other foods to the meal it changes again.  The only way to accurately determine the GI of a meal is to test our own individual blood glucose response to it.

4) THE GLYCEMIC INDEX DOES NOT TAKE SERVING SIZE INTO ACCOUNT:- GI rankings are based on a standard 50g serving of carbohydrates.  They do not consider that you may only consume low amounts of high GI foods (which will result in a smaller blood glucose increase) or large amounts of low GI foods (which will result in a greater blood glucose increase).

However, this problem can be addressed with the glycemic load (GL) which takes serving size into account.  To calculate the glycemic load of a food you take its glycemic index, divide it by 100 and then multiply it by the net carbohydrates in the serving (total carbohydrates minus dietary fibre).  So for example if you ate a 100g unripe banana which had a GI of 30 and contained 15g of dietary fibre the glycemic load would be 25.5 = (30/100 * (100-15)).

Like the GI, the GL breaks foods down into three bands:
- Low GL Foods = Foods with a GL below 11.
- Medium GL Foods = Foods with a GL between 11 and 19.
- High GL Foods = Foods with a GL above 19.

GLYCEMIC INDEX SUMMARY

The glycemic index is a flawed tool but it does have some value when choosing your carbohydrates.  Selecting low GI carbohydrates can help stabilise your energy levels, improve your appetite control and prevent cell damage.  The glycemic index also promotes some healthy food choices such as steering people away from sugars and towards high fibre carbohydrates which have a number of benefits.  However, it can potentially promote the over consumption of fatty products because they generally have a low GI.  Furthermore, there are a number of factors that can change the GI of foods making it a difficult tool to base your diet around.

Overall, the GI is definitely a good starting point when it comes to choosing your carbohydrates.  Whilst it is limited and has a number of problems it can be a useful indicator of both good and bad carbohydrate choices.

What do you guys think?  Is the GI a useful tool despite its flaws?  Are there any better methods you know of for choosing your carbohydrates?  Leave a comment and let me know your thoughts.

Sources:
Glycemic Index (NutritionData.com)
Glycemic Index List (About.com)
What is the Glycemic Index (About.com)
Understanding the Glycemic Index (How Stuff Works)

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What are Carbohydrates?

 

February 23, 2009 By Tom 51 Comments

In a number of my previous articles I have stated that you should go for complex carbohydrates where possible and minimise your consumption of simple carbohydrates.  After thinking about this for some time I realised that I had never fully understood or explained the difference between the two.  That’s why today I am going to be discussing carbohydrates in greater detail.

WHAT ARE CARBOHYDRATES?

Carbohydrates are one of three macronutrients with fats and protein being the other two.  They are made from a combination of carbon, hydrogen and oxygen hence the name ‘carbo’ (meaning carbon) ‘hydrate’ (meaning water which is made from hydrogen and oxygen).  Carbohydrates are your body’s primary energy source.  If they are not needed a small amount can be stored in the liver and muscles as glycogen and the rest is stored as fat.

WHAT ARE SIMPLE CARBOHYDRATES?

Simple carbohydrates (also known as simple sugars) are chemically made of one or two sugars.  There are two main types:

1) MONOSACCHARIDES:- These are the simplest type of sugar hence the name ‘mono’ (meaning one) and ‘saccharide’ (meaning sugar).  Monosaccharides are used to form more complex carbohydrates and there are three different types:
- Fructose:- This is often referred to as fruit sugar because it is found naturally in many fruits and honey (often in combination with glucose).
- Galactose:- This is formed when lactose (a disaccharide discussed below) is broken down during digestion.
- Glucose:- This is often referred to as blood sugar because it is the main carbohydrate that travels through the bloodstream.  It is found naturally in fruits, vegetables and honey.

2) DISACCHARIDES:- These are made of two monosaccharide units that are linked together hence the name ‘di’ (meaning two) and ‘saccharide’ (meaning sugar).  There are many types of disaccharide and some of the most common are listed below:
- Lacctose (Glucose + Galactose):- This is often referred to as milk sugar.
- Maltose:- (Glucose + Glucose):- This is often referred to as malt sugar.
- Sucrose (Glucose and Fructose):- This is often referred to as table sugar or cane sugar.

WHAT ARE COMPLEX CARBOHYDRATES?

Complex carbohydrates are chemically made of three or more chemically linked sugars.  There are again two main types:

1) OLIGOSACCHARIDES:- These are made from a few monosaccharide units that are linked together (usually between three and ten) hence the name ‘oligo (meaning few) and ‘saccharide’ (meaning sugar).  Oligosaccharides are found in various plant foods including onions and wheat.  The human digestive system struggles to break down this type of carbohydrate with 90% not being digested in the small intestine.

Apart from being a carbohydrate, oligosaccharides also act as prebiotics meaning that they support the growth of various bacteria in the large intestine (colon).  These bacteria have a number of health benefits.  For starters they are believed to produce a number of short chain fatty acids (SCFA) and small amounts some of the B complex vitamins.  They are also thought to promote further absorption of certain minerals.

2) POLYSACCHARIDES:- These are made from longer chains of monosaccharides or disaccharides that are linked together hence the name ‘poly’ (meaning more than one) and ‘saccharide’ (meaning sugar).  Although they are made from simple sugars they do not taste sweet.  There are four main main types of polysaccharide:
- Starch:- This is the stored form of carbohydrate in plants.  It can be further broken down in to rapidly digesting starch (RDS) which breaks down in to simple sugars quickly, slow digesting starch (SDS) which breaks down in to simple sugars over a longer period of time and resistant starch which passes through the small intestine and reaches the large intestine (colon) without being broken down in to simple sugars at all.  The speed at which starch is digested also depends on other factors including how processed the food is (processing generally does the same job that our digestive system would do so the more processed a food is the easier it becomes to digest), the starch structure (the arrangement of the sugar molecules that make up the starch affect how easy it is to digest) and how the starch is cooked (cooking time of pasta is believed to affect how easy it is to digest).
- Glycogen:- This is the stored form of carbohydrate in humans and animals.
- Cellulose:- An indigestible form of carbohydrate that comes from the cell walls of plants.  It is better known as dietary fibre.
- Dextrin:- This is produced when long chains of starch are digested and broken down in to shorter chains.

HOW DOES YOUR BODY USE CARBOHYDRATES?

As I mentioned above carbohydrates are your body’s primary choice when it comes to getting energy.  When you eat carbohydrates they are broken down in your digestive tract and then released into the blood as glucose which causes blood glucose levels to rise.  The rate and speed at which they rise depends upon the type of carbohydrate ingested.  Eating simple sugars or RDS causes glucose levels to increase rapidly whilst eating SDS causes sugar to be released in to the blood in a more controlled way and keeps glucose levels stable.

When your blood sugar levels rise your pancreas releases insulin, a hormone that helps your cells take glucose from the blood and either use it for energy, store it as glycogen or store it as fat.  As your body’s cells take glucose from the blood and your blood sugar levels become low your pancreas stops releasing insulin and starts releasing glucagon.  Glucagon is a hormone that helps your liver convert stored glycogen back in to glucose and release it in to the bloodstream.

If your glycogen stores become depleted your body can then convert protein and fat in to glucose through a process called gluconeogenesis.  However, this is a much more complicated and inefficient process.  On top of this fat’s primary function is to help protect the cells and vital organs whilst protein’s primary function is to help repair and build them.  If your body uses these macronutrients for energy then they cannot perform their intended functions properly.  For these reasons carbohydrates are your body’s preferred energy source.

WHY DOES IT MATTER WHICH TYPE OF CARBOHYDRATE SOURCE I CHOOSE?

So far I have explained the different types of carbohydrate and also how your body uses carbohydrates.  With the exception of fibre, oligosaccharides and resistant starch all carbohydrates end up being broken down in to sugar (glucose) which then provides your body’s cells with energy.  So if they all end up as sugar why should you worry about which type of carbohydrate you consume?

Well although all carbohydrates eventually become sugars some are digested a lot more quickly than others.  Carbohydrates that are easy to digest are released in to the blood rapidly and cause a quick surge in glucose levels.  Your body responds to this surge by releasing additional insulin which then causes your glucose levels to crash.  This can result in fluctuating energy levels, increased fat storage, poor appetite control and in the worst cases damage to your vital organs.  Constrastingly, carbohydrates that are more difficult to digest are released in to the blood slowly which means glucose levels remain relatively stable and the above problems are avoided.

Also certain carbohydrate sources are more nutritionally dense than others.  For example, table sugar provides you with carbohydrates and not much else.  However, a fruit or vegetable provides you with carbohydrates, fibre and vitamins meaning that you get much more nutritional value from a 100 calorie piece of fruit than you would from 100 calories of table sugar.  Therefore, slow digesting, nutritionally dense carbohydrates are the best choice for your body.

CARBOHYDRATE SUMMARY

In the past I referred to complex carbohydrates as those that were high in fibre, rich in vitamins and minerals and more difficult to digest.  However, after researching and writing this article I realise that this was a mistake.  Whilst this definition is true of some complex carbohydrates it is not true of them all.  All carbohydrates (with the exception of fibre, some oligosaccharides and resistant starch) are essentially sugars.  Some complex carbohydrates actually break down more quickly than simple carbohydrates.  Instead of looking at simple and complex carbohydrates we should instead be looking to consume carbohydrates that digest slowly and are rich in fibre, vitamins, minerals and other nutrients.

In my next few articles I am going to be discussing some of methods you can use to choose the best carbohydrate sources.  Until then I hope that this article has given you a good understanding of the different kinds of carbohydrates and cleared up the confusion surrounding simple and complex carbohydrates.

Now I want to hear from you guys.  Do you agree with what I have said about carbohydrates?  Are you currently consuming the right type of carbohydrates?  Let me know by leaving a comment.

Sources:
Carbohydrate Basics (How Stuff Works)
Understanding Carbohydrates (About.com)
What’s the Difference between Simple and Complex Carbohydrates? (About.com)

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