Should I Cut The Carbs To Lose Weight?

For many of us, gaining weight or keeping weight off can be something that sits at the forefront of our mind.  We are bombarded with information that maintaining a lean body mass is better for our overall health and that it significantly reduces our risk of a range of health issues.  So, we try to exercise more, and we want to make optimal dietary choices.  One website tells us that a low-carb diet is the way to keep those extra pounds off and another tells us that keto is the only way to go.

But do we really need to cut the carbs if we want to maintain a healthy weight?  Let’s take a look.

What Are Carbohydrates?

Carbohydrates are one of the macronutrients, along with fat and protein.  The main function of a carbohydrate is to provide energy and they are the preferred source of energy for the brain.

When eaten, carbohydrates are broken down into sugar and transported wherever needs energy.  So that quick HIIT session, is fuelled by carbs!

When our energy demands have dropped (we’ve stopped our workout) or we ate more carbs than the body needed, they get stored in muscle and liver tissue as glycogen, but they will also get shuttled to fatty tissue.  When we have an energy demand again, it is liberated for use at a later stage.

Carbs can be used very efficiently for energy, which is why when we are performing at high intensities, they are the preferred source of fuel.  We can use fat for fuel, but this process needs more oxygen, so when we are at our limit, we can’t take enough oxygen in to help the process.  Fat is great if we are heading out on a long hike or are running a marathon because we’ve got a steady intake of oxygen.

So, if carbs can be stored when they’re not used, surely this means carbs make me fat?

Yes, this is true.  Unused carbs do get stored as fat.  The body created this mechanism so we could eat in abundance when we had access to food and save some for later when food was scarce.

But any macronutrient in excess of energy needs will contribute to unwanted fatty tissue gain.  So, we can’t solely demonise carbs.

Does this mean I should cut the carbs?

Not necessarily.

The thing to consider around weight gain is energy balance.  We tend to gain unwanted weight if our nutrient intake is in excess of our energy needs.  In short, we gain unwanted weight when we eat more than we use.

However, weight gain is not in fact this simple, and we also have a caveat to consider with the function of carbs.

Let’s start with the complexity of weight gain.

There are hormonal considerations around obesity and weight gain.

All of the fat found in cells is stored in the form of triglycerides. Fatty acids are converted into triglycerides for storage and then for fat to be used as energy, they are freed back into fatty acids and glycerol. Getting fat is the process where triglycerides are created more quickly than they are broken down.

This flow of fatty acids is regulated by a range of enzymes and hormones. This isn’t surprising when we consider the role of growth hormone, it is what drives the growth of children and adolescents.  In addition, consider bodybuilding.  Steroid hormones are used to increase bulk.  Furthermore, if you take a trip down memory lane, chickens were injected with hormones in the 50’s to increase their size.

It seems that, on a simplistic level, certain hormones cause fat cells to suck up fatty acids more readily than they otherwise would or slow down the rate at which triglycerides are converted back.  The hormonal impact on weight gain is incredibly complex and if you are struggling to maintain your preferred weight, pop to see your healthcare provider and discuss hormonal testing.

The other idea gaining momentum is that obesity is related to gut health.

Studies have demonstrated that transplanting the microbes from an overweight mouse to a lean mouse, would subsequently make the lean mouse, fat.  The reverse is also true.  Now we’re not advocating faecal transplants to the general population, but it highlights an interesting concept that the microbes found in our guts play a role in the energy extracted from the food we eat.

There are several things that can influence the community of microbes found in our gut from the way we were born to how we were brought up.  Stress also influences the community in our gut, along with the diet we choose to eat.  Those who eat a typically western diet, high in saturated fat and low in fruits and vegetables often have poorer gut health than those who regularly eat their 5-a-day!

This leads us nicely to the other function of carbohydrates that we mentioned early.

Carbohydrates are a source of fibre

Under the umbrella of carbohydrates, you will also find fibre.  Fibre is the indigestible part of the food.  What this means is that it finds its way through our digestive system relatively untouched until it gets to our large intestine.  Here, the microbes in our gut have a feast!  Like all things, what gets fed, survives, and so if we want a healthy community of microbes in our gut, we need to feed them!

  • Fibre supports our gut health by promoting regular motility – it helps things move through the digestive system as they should.
  • Fibre supports balanced blood sugar levels – simple carbs are relatively low in fibre, but complex carbs take longer to be digested and so there is a steadier rise is blood-glucose levels.
  • Fibre supports our mental health – those microbes found in our gut also talk to our brain. When we have a certain community of fed and thriving bugs, compounds are released which supports our mood and feelings.  When there are low levels of certain microbes (because they haven’t been fed), those compounds are low, and we know that this can contribute to feelings of anxiety and depression.

So, the issue with cutting carbs is that you inadvertently cut fibre too!  And fibre is a true friend.

So where does this leave us with our carbs?

The bottom line is that we may want to look at cutting the simple carbs but not the complex carbs.

Simple carbs are those that are generally heavily processed.  This means they don’t take much digestion and glucose is released into the bloodstream relatively quickly. We’re not denying that simple carbs can be helpful if you are a competing athlete or have a particularly high-energy exercise routine.  But remember if you aren’t using the energy released, then it will get transported and stored for a later date.

Complex carbs on the other hand, take longer to digest, and they provide fibre for your gut.

The general rule of thumb is that 45-65% of your dietary intake can be carbohydrates but opt for complex carbs.

If you think about your plate, load half of it up with veggies, a quarter with starchy veggies like potatoes or rice and the other quarter with a protein source.

For those of us who are active, use complex carbohydrates in your mealtimes and if you are particularly active, simple carbs can be a useful energy source if and when you feel you need it.

If you are worried about weight gain, carbohydrates aren’t the enemy.  We just need to be more mindful of the type we are eating.  Remove processed foods where possible and be mindful of the total number of calories being eaten in comparison to daily energy expenditure.