In recent years protein has become a hero macronutrient. Long have carbohydrates been vilified, sparked from beliefs they make us fat and fueled by the rise of Paleo and low carbohydrate diets (now thankfully falling somewhat out of favour). Although fats are generally now not all considered bad (hello to the avocado generation), deep-seated beliefs stemming the 80’s low-fat diet craze and the falsities surrounding their link to heart disease, still mean we approach with caution. Protein on the other hand… it’s been boosted in special product variations of everything from our Snickers bars to our Weetabix, and we’re here for it!
Let’s start with the basics. Protein is an essential part of our diet. When eaten, it stimulates protein synthesis for both muscle growth (when combined with resistance training), and general growth and repair. It’s also vital for many biological processes, and a number of key health markers including: contribution to bone mineral density, maintenance of neurotransmitters that regulate brain functioning and mood, hormone function, satiety and hunger regulation with links to blood sugar regulation and associated weight and fat management. If weight management is a concern to you, making sure you’re eating enough protein will help you feel satiated, keep your blood sugars more stable avoiding the roller-coaster that leads to the biscuit tin, and help to maintain lean muscle while in a calorie deficit.
So, How Much is Enough?
The NHS recommends women eat 45g of protein a day, and men consume 55g. Of course this is extremely general and doesn’t take into account the infinite variables of body size, activity levels, physical and performance demands. The NHS just want to keep us all ticking over. The research I’ve been exposed to instead recommends a minimum of 1.6g of protein per kg of bodyweight as a way of optimising protein synthesis and maintaining lean body mass (for example: the ‘average’ UK woman weighs 70.2kg according to the ONS, so should consume 112g of protein per day. The NHS is recommending 0.65g per kg, based on this average woman). Combining this higher protein intake with resistance training will stimulate protein synthesis as the muscles repair and laydown new fibres during recovery. Some studies show those who are extremely active might benefit from as much as 2.4g per kg of bodyweight, per day… though I wouldn’t recommend this to anyone I work with. Personally, the 1.6g per kg ratio makes sense to me: it’s manageable and will certainly help keep your satiety in check, helping maintain lean body mass. This is particularly important if you’re on a calorie restricted diet, as it will encourage your body to burn fat for fuel and maintain muscle.
Older adults build up ‘anabolic resistance’ which means they need more protein than younger adults to stimulate protein synthesis. This anabolic resistance combined with age-related muscle loss (sarcopenia), means that older people need to be especially mindful of protein. After the age of 30 (!!) we start to lose 3-5% of our muscle mass per decade on average. This results in a lower resting metabolic rate, and in the long-term, weakness that can result in higher rates of fractures. The takeaway: weight-baring and resistance training, combined with sufficient protein is vital at any age – tell your grandma!
It's important to mention that you can have too much of a good thing. High protein diets put a strain on your kidneys, and if combined with high amounts of saturated fat are associated with heart disease and colon cancer. Derive your proteins from lean animal sources, fish, and plant based sources as part of a balanced diet rich in fruit and vegetables and definitely carbohydrates!
Timing, Timing, Timing
If you do decide to aim for the 1.6g/kg protein target it will be infinitely easier to achieve by spreading protein intake throughout the day (especially if you’re vegetarian/vegan and having to think more carefully about how to achieve this target). Research suggests that consistent protein spikes every four hours stimulates protein synthesis, preventing the body from slipping into protein breakdown. Using our 112g example as a target, realistically the protein spread might look like: a 3 egg breakfast omelet, a lunch of chicken breast with quinoa, snack of high protein yoghurt such as Fage 0%, and dinner of a fish fillet with brown rice.
Complete Proteins (Veggies and Vegans, listen up!)
Amino acids are the structural units that make up proteins. There are over 20 of these individual units. When we eat a protein, the body breaks it down into the individual amino acids it contains, to use for various functions. Nine of these ‘essential’ amino acids the body cannot create on its own, and must come from the diet. You may have heard the term ‘complete protein’ being banded about, especially in the context of a vegetarian or vegan diet. That’s because not all protein sources contain all nine essential amino acids, and those that do are typically from animal products (meat, fish, diary products and eggs). While there are some ‘complete’ plant-based foods (such as quinoa and chia seeds), most lack one or more essential amino acids, so it’s important to consider your protein sources more carefully. The general advice now is to include a range of plant-based proteins across your day while on a vegetarian or vegan diet, rather than concerning yourself with creating a complete amino acid profile at every meal.
Food manufacturers have caught onto the protein craze in a big way! Highly processed, low nutrient foods from chocolate bars to breakfast cereals are using the word protein as a sticking plaster to cover up their poor nutritious credentials. Approach these products with caution. Often the protein content is far lower than you might expect, and certainly no match for an equivalent alternative food choice. For example, Graze Protein Oat Bites contain only 4.4g per serving, which given their small size is understandable, but is likely to be much lower than expected from a bar with ‘protein’ in the title! Compare this to a calorie equivalent serving of Fage 0% yogurt and blueberries, which would contain over 20g of protein, and I bet your starting to re-evaluate that ‘protein’ cereal bar!
I personally believe there’s a place for protein supplements such as powder or bars when on the go, or as a convenient protein boost for some. I recommend you look for products with the fewest ingredients in general, which are free from fillers, artificial ingredients and chemicals you can’t pronounce! And if you can get enough protein from a wholefood diet, do that!