Glucose is essential to our lives as humans. Energy transfer depends on it and tissues such as our brain and red blood cells cant make their own glucose.
Fun fact, our brain needs roughly 130g of glucose per day to function! We mostly get this from our diet, but when our carbohydrate intake is lower we can get this from gluconeogenesis and ketosis to provide what we need.
There is no single “Best Diet”.
There is also no correct amount of carbohydrate that is the same for everyone.
Carbohydrate factors will depend on;
- How big or small you are;
- How much lean mass or body fat you have;
- How active you are;
- How intense, long lasting or frequent that exercise is;
- How old you are, and what stage of life you’re at;
- Intake levels of other macronutrients;
- What foods you like, tolerate and prefer to eat;
- What you want to do.
For example, a bodybuilder looking to bulk up in size vs a 73 year old woman taking up yoga will need less overall energy intake and thus carbohydrates. When it comes to carbohydrate intake, there is a distribution of how this intake will vary. There are a small percentage of people who do well with a higher amount of carbohydrates, another small percentage who do well with a lower intake of carbohydrates and then the rest of us who are somewhere in the middle!
But lets focus on these key points for now:
- Humans evolved to eat a varied and seasonal diet. We thrive best on a mix of carbohydrate types that occur naturally in different types of food.
- We want to be eating slower digesting carbohydrates most of the time.
- We can easily have access to these different types of carbohydrates if we eat a good mix of whole, less processed foods.
- Occasionally, faster-digesting lower fibre carbohydrates can be helpful, especially for athletes or people looking to gain weight.
Not all “Carbs” are created equally! Whilst it is true that when we ingest the carbohydrates they generally tend to meet the same end, the actual steps in which they end up as glucose will differ. This in turn will create different effects in the body.
Lets compare a couple of examples.
- Cellulose, which technically is a carbohydrate, isn’t something we use for energy at all! The bacteria in our GI tract love to eat this stuff, and then we just excrete the rest. As fibre, it binds to other things in our intestines such as fat soluble hormones or other dietary fats.
- A highly branched chain of amylopectin must be broken down slowly in our small intestine. It will release glucose gradually.
- A teaspoon of sugar in your morning tea or coffee will be super easily broken down into glucose and fructose for quick disposal in our liver and possibly bloodstream.
But in general, we should be looking to eat mostly complex carbohydrates from whole food sources!
Fibre comes in a couple of different forms, soluble and insoluble!
Our bodies cant digest these guys, but they do have crucial functions! The bacteria in our gut love to ferment them, producing short chained fatty acids like acetate, propionate and butyrate. There’s evidence to show that these fatty acids can provide various different health benefits!
Insoluble fibre is mostly found in the structures that make up the plant’s rigid cell walls. This includes vegetables such as celery, root vegetables, dark leafy green veg, fruit and vegetable skins and nuts.
Soluble fibre gets its name simply because the molecules are water soluble. Soluble fibre is found in oats, bran dried beans, peas, nuts, barley, flax, chia, fruits like oranges, bananas, blueberries and apples, and vegetables such as artichokes, tomatoes and carrots.
Soluble fibre has an important function with bile acid. Instead of bile acid being recycled, it will be excreted in the stool. This helps decrease cholesterol levels.
And so, fibre has the following benefits.
- Helps us feel fuller for longer
- Boost overall gut health
- Lower risk of colon cancer
- Lowers our blood lipids and cholesterol
- Keep things moving through our GI tract.
Lets keep the complex carbs simple!
When it comes to the carbohydrates themselves, we suggest keeping them as complex as possible! As often as you can, choose less processed whole foods with slow digesting carbohydrates such as complex starches and fibre.
But when it comes to programming for yourself, keep it simple!
Don’t get lost in nutrient timing, GI lists if you aren’t eating your veggies! Instead start with the real priorities make sure you’re eating the right foods, in the right amounts and for the right reasons