For some people, carbohydrates have a bad reputation. There seems to be and idea that carbs are bad for you, unhealthy and you should feel guilty having consumed them.
So, here we will see whether carbs are part of a balanced diet, or he who shall not be named!
Structure
First, let's have a look at what carbohydrates are. Carbohydrates are one of four macronutrients; those being carbohydrates, protein, fat, and alcohol (that's right alcohol too..... it has no real nutritional value like the others, but that's for another post).
Carbohydrates are found only in plant foods (with the exception of galactose/Lactose found in milk).
Fundamentally, in their simplest form carbohydrates are single sugar units (Monosaccharides), and the 3 nutritionally important types of sugar are Glucose, Fructose and Galactose (the latter found only in dairy products). These can then connect (bond) as a pair to form Disaccharides (2 sugar units). Both Monosaccharides and Disaccharides are categorised as simple sugars. See a breakdown in the figure below.
Oligosaccharides (3-10 sugar units), and Polysaccharides (more than 10 sugar units) are categorised as complex carbohydrates.
There are 3 dietary forms of Carbohydrates:
Sugar - (simple sugars) - Monosaccharides and Disaccharides, the quick release (fast digesting) energy.
Found in: Table sugar, honey, jam, sweets, cakes, biscuits, glucose/sports gels. chocolate, fruit juices, fizzy drinks.
Starch (complex carbs) - Polysaccharides and Oligosaccharides, the slow release energy.
Found in: Grains, wheat, rice, potato, sweet potato, vegetables
Fibre (Complex carbs) - Categorised as the indigestible portion of the plant, generally made up of polysaccharides that have no open end which prevents them from being digested.
Found in: Fruits and vegetables (and their skin), oatmeal, beans, brown rice, whole grain wheat, nuts and seeds.
Function
So why do you actually need them? The main function of carbohydrates is to provide energy. They are the body's primary energy source, for muscles, cells, and in particular the brain which can use around 20% of available glucose.
They are technically classed as a 'non-essential' nutrient because although they are typically consumed through food and sports drinks, they can also be converted from other nutrients such as protein (Gluconeogenesis) if needed.
They are also found around the body in the blood (to be used wherever they are needed), or stored as glycogen in the liver (to replenish blood sugar) or in the muscles (to be used in those specific muscle cells).
However, not all carbohydrates are the same and the type/form in which they come will change their role in the body, and the physiological effect they have:
Sugars - These simple sugars are already in their usable single unit or almost usable paired unit form, so can be used immediately as fuel. This is useful when doing short and intense or long duration exercise to replenish your available glucose to help maintain performance output (typically glucose gels), but more commonly what is consumed are highly processed foods and snacks with added sugars, and rarely during exercise but rather alongside a sedentary lifestyle. This can cause spikes in your blood sugar and if consumed frequently in excessive amounts, paired with a sedentary lifestyle, can contribute towards developing type 2 diabetes.
Starch - These are the complex carbs commonly referred to as slow release energy, due to the time it takes to break down the longer chains into the absorbable single sugar units (Monosaccharides). These are typically better for maintaining energy levels and a more levelled out blood sugar level over a longer duration due to the steady 'drip-feeding' of glucose. This helps to mitigate that glucose spike and then 'crash' that we can feel after consuming something rich in sugar.
Complex carbs are also an important part of exercise performance as they are the more efficient fuel, and are almost essential for long distance sports or exercise lasting a very long time, like long distance running or cycling.
Fibre - Although not deemed an energy source, it aids in digestion as well as other functions. There are two types of fibre (soluble and insoluble) which collectively help regulate digestion, manage hunger levels and keep us fuller for longer, slow digestion (helps with nutrient absorption), manage blood sugar spikes and can contribute the reduction of the 'bad' cholesterol LDL (Low Density Lipoprotein).
Carbs and weight gain
Let me start this section by saying: Carbs do NOT make you 'fat' or gain weight.! With that out of the way, let's briefly explore the nuance behind that statement.
As most of you know by now (if not, check out my previous posts), calories in vs calories out is the ultimate determiner of weight loss and gain, if you eat more than your body needs you'll gain weight and vice versa. In terms of calories per gram, we have carbohydrates and protein at 4 kcal/g, fat at 9 kcal/g and alcohol at 7 kcal/g, so carbs (as a nutrient) are actually at the low end.
Now, the nuance!! As discussed above we now know carbs encompass sugars, starches and fibre, which all behave differently in the body. Sugars CAN be a problem for weight gain or people trying to lose/manage their weight, as we saw in the above section, sugars are ingested in single or paired sugar units which means very quick absorption compared to other forms of carbohydrates; so if that energy dump is not used almost as quickly, your insulin will get to work and put most of those bad boys into storage (converted to fat, after glycogen has been replenished).
When you combine this with how these types of foods tend to be hyperpalatable (tasty and easy to throw back), you can see how these can have a very large impact on weight management.
With all this being said, however, for some reason the 'carbs are evil' sentiment tends to be directed at the starchy food group.
Some starches like bread and pasta can cause bloating for some people (perhaps because of a gluten sensitivity, but I'm not qualified to say either way) which may lead to the weight gain idea, but no actual weight has been gained necessarily.
What might be something to note is that some starchy foods like rice, pasta, and bread can potentially be more calorie dense than we realise. It can depend on the type and the brand you purchase, so it's sometimes worth having a quick look at the calories on the nutrition label. So even though 1 gram of carbs has 4 kcal/gram like protein, those carbs just might be more densely packed in a particular food.
Example: 100g of Tilda basmati rice has ~351 kcal, whereas chicken breast can range from 137 kcal to 250 kcal per 100g (depending where you look).
This can be important to know when you compare it to protein foods (provided they are the leaner sources of protein) such as meat, fish and eggs, or even just highly fibrous vegetables, which also tend to be less calorie dense and quite satiating, due to them taking longer to digest.
Some starchy carbs, while rich in fibre, can also be quite palatable themselves, making them easier to over eat, especially when paired with dressings, oils, cheeses, sauces etc. Potatoes, however, are one of those starchy carbs that (when not drowned in butter and cheese) are very satiating and on the lower end of calories per 100g.
Again, starchy carbs are not a problem, but keep the source in mind depending on your goals.
Summary
So to wrap that all into a neat little paragraph. Sugar, starches and fibre are all carbohydrates and they have different effects on the body.
Starches and fibre are the most important forms when it comes to helping with performance and digestion, and sugars should only be consumed in moderation, although they can also have their uses for sports and exercise performance.
Carbs don't cause you to gain weight as this will only happen when you're in a calorie surplus.
Weight loss as a process can be made more manageable and a little easier with a slightly reduced carbohydrate intake, mostly sugars but also some starches. But remember, more fibre will actually help the process. so no need to cut the carbs, just choose wisely!
Carbohydrates are not the boogieman and are an important part of a balanced and well planned diet, so enjoy.
Hopefully that's cleared things up and you now have a better understanding of carbohydrates, and you can get out of the situation-ship with carbs to a healthy relationship.
Keep an eye out for further posts on health and fitness
If you feel you need an extra helping hand with your journey, definitely reach out.
Thanks for reading :)
Comments