In the first part of this series we looked at fats; In the second part in this series of blogs we look at the 2 other macros: protein and carbohydrate.
Protein – muscle food
Protein makes up much of the bodies tissue and organs and mostly comes from animal sources, although there are plenty of plant sources as well (e.g. nuts and pulses). Getting a moderate amount of protein in is important for weight management1, repairing tissues and building muscle. You’ll want to eat between 0.3 to 0.8 grams of protein per pound of bodyweight daily (potentially more if you’re exercising). Protein satiates much more fat and more than carbohydrate2 – but because eating too much triggers inflammation and insulin response3, eating a lot of protein isn’t the best way to control appetite or reduce weight. Converting too much protein to amino acids also places a burden on the liver and can lead to kidney problems3,4.
The best sources of protein are low mercury wild fish (sardines, anchovies, sock-eyed salmon)5,6 or grass fed organic beef or lamb. These sources contain high levels of omega 3 fats7,8 and the high protein content are particularly good for when building muscle. When eating chicken or turkey, go organic and free range and go for low fat cuts as white meats tend not to have such a good fatty acid profile9. Sources of protein to avoid are proteins based on soy, cheese, high mercury or farmed seafood and meat raised on grains and treated with antibiotics.
Carbs are primarily used for energy in the body. The simplest form of carbohydrate is glucose or fructose. Since these can become toxic to the body at certain levels, they are converted and stored as glycogen or fats and are converted back to glucose when needed10,11. Carbohydrates come in several forms:
- Simple sugars: glucose, sucrose and fructose. Common sources of these include fruits, sweets and processed foods. You’ll want to limit your exposure to these as they tend to get converted to fats straight away. They have a high glycemic index – a measure of how high blood sugar spikes after eating. Eating them causes a surge in blood sugar, insulin is released and lowers the blood sugar and leads to a crash in energy. You may have experienced this crash as a food coma.
- Complex starchy carbohydrates. These are sugars that are connected together into a large complex starchy structure and there are 2 types: unrefined and refined. Unrefined are found in brown wholewheat pastas, breads and brown rice. Refined are found in white breads and pastas. The process of refining unrefined carbohydrates reduces the complexity of their structures – as a result when eaten, refined carbohydrates cause a blood-sugar spike and get converted to fats. As unrefined carbs have a more complex structure they are digested into simple sugars as easily and have lower glycemic indexes.
- Complex fibrous carbohydrates are found in vegetables with large fibrous structures. As much of the fibre in vegetables are indigestible, these pass through the digestive system without being absorbed.
How much carbs you eat depends on your activity levels and exercise regime. For example, if you’re on a HIIT program, you’ll want to eat carbs after work outs to aid lean muscle building12,13. On days you’re not exercising you’ll want to keep the carbs low to aid fat loss. For a general healthy diet, it’s best to avoid sugars and refined carb sources as these lead to higher blood triglyceride (fat) levels which contribute to cardiovascular disease14,15.
Come back for the next in the series where we’ll turn our attention to macro balance.
I’d love to hear your thoughts – please leave me a comment below.