Will carbs make you fat?

"Carbs make you fat!", "Cut carbs and you'll lose weight!", "If you eat carbs after 6 you'll get fat!".  I hear statements like these an awful lot. Too often. Thrown around like facts, they're so commonplace now that a large amount of the general public have developed a phobia of carbohydrates, despite not really knowing what they are or what they do for your body.

What are carbs & their function

Things might get a little sciencey here - but not too much, I promise. The definition of a carbohydrate is: "a biological molecule consisting of carbon, hydrogen & oxygen atoms. Practically speaking though: tasty food like potatoes, rice, pasta, bread, biscuits, fruit, sweets....

Carbs, be they wholegrain, organic quinoa or Haribo Tangfastics, are broken down in to glucose. Glucose provides your body & brain with energy. Where quinoa & tangfastics differ is: 1) the nutrients they contain and 2) how they're broken down by your body. Both will ultimately end up as glucose; the difference between the two is the chemical structure - how quickly the CHO molecule is broken down and the sugar is absorbed and digested. Tangfastics are simple carbs, broken down quickly and released into the bloodstream whilst quinoa is complex and is released over time.

Carbohydrates contain 4 calories per gram. Carbs are your body's main source of energy and so your "requirements" will vary depending on your activity levels. If you're sedantry, sitting at your desk all day typing & sitting on your arse all night watching back to back Netflix, chances are you don't need 300g of carbs to fuel you. However if you're active, either through deliberate exercise (training) or through your lifestyle (work/hobbies) then you'll need a higher level or carbs to ensure you've got the energy for optimal performance.

During digestion, all carbs are broken down into glucose. The body uses whatever glucose it needs immediately and then stores the rest as glycogen in your liver and muscles. Glycogen is a complex polysaccharide that your system converts back to glucose when carbohydrates from food are not available. For example, during a vigorous workout, your body will turn to your glycogen stores to get the energy it needs to fuel muscles. As you exercise and burn through your stores, your glycogen will gradually deplete. Your brain too, will rely on liver glycogen to fuel it throughout the day. 

So, excess glucose is converted to glycogen & is stored in the liver and muscles for future use. If your blood contains even more excess glucose again, then the body will convert it & store it as fat - which is why it's important to balance your carb intake with your activity levels. In the images above you'll see what I ate the day of my powerlifting meet, when my body was under immense pressure to perform. A combination of slow release carbs, in the form of wholewheat bread rolls & simple, fast release carbs in the form of Haribo & Jaffa Cakes made 100% sure I had enough energy (glucose) for maximum effort lifts.

Carbohydrates fall into three basic categories: sugars, starches and fibre. Simple sugars (monosaccharides) like the Krispy Kreme are digested very quickly. More complex carbs are broken down through a series of enzyme reactions & take longer to digest - that is, they take longer to be broken down to sugar.

Krispy Kremes whilst drinking beer & watching cricket... definitely not necessary (but damn tasty!)

Krispy Kremes whilst drinking beer & watching cricket... definitely not necessary (but damn tasty!)

Carbohydrates are the only macronutrient we can live without. However, carbs have positive impacts on hormones, heart health, physical & mental performance and make life a hell of a lot tastier.

But carbs make me fat?

pizza order

Carbs don't make you fat. Neither does fat. The only thing that makes you fat is eating more calories than you need. If you're eating too much of anything, you'll gain weight. Where the confusion lies is that people will struggle to eat 3,000 calories of chicken, brocolli & kale. It's quite easy to get through 3,000 calories if you're eating chicken korma, naan bread & Ben & Jerry's though. As long as your mindful of what you're putting in to your body and have a grasp of the basics of nutrition there's no reason to avoid carbs.

Do try to be mindful of the quality of the carbs you're taking in though. A sweet potato will contain fibre & vitamin A whereas Ben & Jerry's is pretty void of nutrients. You'll also find it a hell of a lot easier to wolf down 1,000 calories of icecream!

Some people may not deal well with certsain carb sources. Coeliacs for example, have adverse affects to gluten. (Gluten is actually a protein, which is found in many cereal grains.) If you think you may have an intolerence do not diagnose yourself - go to a GP or dietician.

What about carbs after 6pm?

Most propronents of bro-science, who preach about avoiding carbs in the evening, do so because they believe that, since you're likely to be winding down - watching TV and then going to bed - your energy demands will be low, your metabolism will slow down and these carbs will be stored as fat. Seems logical... but is very wrong.  It does vary, but your sleeping metabolic rate can be the same - if not higher - than your resting metabolic rate. Your body uses periods of sleep and inactivity to repair & grow.  The more fuel available to them, the better the recovery - especially if you're resistance training or have a demanding lifestyle.

It depends on the individual, their overall diet & their activity levels, but after a day of walking, working, training and general existing, you're likely to have utilised your blood glucose levels & tapped into muscle and liver glycogen. As you sleep, your brain is extremely active and demands energy. Eating carbohydrates later in the day is effectively topping up your glycogen stores to ensure your recovery is optimal. If you choose not to eat your carbs at night, you can do so at breakfast. Studies have shown that it's irrelevant when you consume your carbs (and food in general) so do whatever suits your lifestyle.

Cake is "unhealthy" though...

30g of Sugar - the same as a can of Coke. Yes, these have vitamins, but little to no fibre and, for those concerned with Insulin spikes, have the same effect on the body. Definitely not for diabetics....

Simple carbohydrates contain just one or two sugars - Single sugars such as fructose (found in fruits) and galactose (found in milk products) are called monosaccharides. Carbs with two sugars, such as sucrose (table sugar), lactose (from dairy) and maltose (found in beer & some vegetables), are called disaccharides.

Sweets, fizzy drinks & confectionary, for the most part, are made up of simple carbs. These foods tend to be void of vitamins, minerals or fiber. Because of the lack of nutrients they contain, calories from these sources are known as "empty calories" and, due to the ease at which they're consumed, can lead to weight gain. Juices & smoothies, marketed as healthy, are essentially liquid sugar but do contain vitamins.

Complex carbohydrates (polysaccharides) have three or more sugars. Whole grains, cereals, vegetables & pulses are common sources of complex carbs. As well as delivering slow-release glucose, these sources are rich in a variety of micronutrients & vitamins, as well as dietary fibre.

complex carbs take longer to break down to glucose, meaning glucose is released over time, as opposed to introducing simple glucose straight into the bloodstream.

complex carbs take longer to break down to glucose, meaning glucose is released over time, as opposed to introducing simple glucose straight into the bloodstream.

While all carbohydrates function as energy sources, simple carbs cause more immediate bursts than complex carbs because of the speed at which they are digested. Simple carbs can lead to spikes in blood sugar levels and sugar highs, while complex carbs provide slow release, sustained energy. When glucose enters the bloodstream, the body produces insulin to shuttle it to tissue - muscles (if needed), fat (if there's excess glucose in the blood) & the liver. Simple sugars trigger a surge (or a "spike") of insulin to control the sudden introduction of glucose. There is ongoing research on the potential negative effects of insulin spikes as it's believed that taking in simple sugars too often can lead to type 2 diabetes/metabolic sydrome.

What is fibre and why do I need it?

Fibre is a form of carbohydrate. It's an indigestible element foud in plants that offers no calorific value. There are numerous benefits - it aids digestion, regulates bowel movements, provides fuel for bacteria in our intentines & can slow the release of simple sugars when present in the stomach. Recommended daily intake varies, but aim for ~30g of fibre per day and you should be good!

High-fiber foods include:

fibre one
  • Whole grains, such as whole wheat and brown rice as well as whole-grain breads, cereals, and crackers
  • Beans and legumes, such as black beans, kidney beans, and garbanzo beans
  • Vegetables, such as broccoli, Brussels sprouts, corn, potato with skin
  • Fruits, such as raspberries, pears, apples, and figs
  • Nuts and seeds

Hopefully this article goes some way to alleviating your fear of carbs. If you're sedantry it may be worth considering cutting back. On the flip side, if you're an active person you might consider upping your carb intake. Whichever you are, I encourage you to be mindful of what you eat... are you getting enough fibre? Are you getting in enough nutrients? Are you drinking enough water? Should you get that burger without the bun today? Maybe tomorrow will be a full burger day...

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