Why you should prioritise protein for weight loss success

Weight loss can be very challenging. If you’re trying to lose weight, or you’ve tried in the past, does the following sound familiar?

You make a lot of changes, you’re more active, and you clean up your diet. Healthy foods are the only things on the menu, and you always cook from scratch. You start to lose weight, but you feel hungry all the time, and you get cravings. It’s tough! You’re rarely satisfied by your meals and end up overeating to satisfy your hunger. Is this you?

You might just be eating the wrong foods. Or, to put it another way, not enough of the right foods. What am I talking about? I’m talking about protein. There are many reasons why you’ll improve your chances of successful weight loss if you consume more protein. In this post, we discuss four reasons why you should prioritise protein for weight loss success.

It’s satisfying

Research has been done to investigate the ability of various foods to satisfy hunger. By looking at the content of the foods tested, the researchers were able to come up with a formula that predicts whether a food will be satisfying.

What they found is that, per calorie, foods containing protein and dietary fibre were more satisfying. By implication, foods that are low in protein and low in fibre will not be satisfying. Foods that have a higher liquid content are also more satisfying than foods with low liquid content.

As an example, consider a snack pot consisting of chicken breast and lentils. That ticks all the boxes for protein, fibre and liquid; it’s going to keep you going for a reasonable length of time. Now consider the equivalent number of calories in rice cakes, a popular dieter’s snack choice. Those tick none of the boxes and aren’t going to fill you up or satisfy you for long.

As another example, for breakfast, consider Greek yoghurt and fruit. Then compare that with toast and butter. Which choice do you think will fill you up more?

As an aside, notice how the filling foods are also healthier.

So, what’s the implication for dieting? Make sure that for every meal and snack, you prioritise protein for weight loss success. Before you decide what to eat, think about how you will provide the protein for that meal or snack. Ensure that every meal and snack has a decent chunk of protein.

It will spare your muscle

When you lose weight, you can expect to lose muscle if you take no specific action to preserve it. Some studies have shown that losses in fat-free mass can account for as much as 35% of total weight loss, with most of that coming from muscle. That’s bad news because muscle burns calories.

It’s estimated that every pound of muscle burns between 6 and 7 calories a day. If you lose three stones overall and 35% of the lost weight is fat-free mass, that could be as much as 15lbs of lean tissue. If most of that is muscle, say 12lbs, then you’re going to lose the ability to burn around 84 calories a day compared to if you’d retained all that muscle.

It doesn’t sound much, but it amounts to over 30,000 calories a year. With a 3500 calorie deficit being equivalent to a pound of fat, that’s around 8 to 9 pounds of fat you could accumulate in a year if you fail to preserve your muscle.

Weight loss and regain

But it gets worse because if you regain the lost weight, you’re more likely to accumulate fat than muscle. So, if you tend to go through cycles of weight loss and weight regain, you could be losing muscle and then replacing some of that muscle with fat every time you gain the weight back. If you do that repeatedly, you’re going to accumulate a lot of fat and lose a lot of muscle. You’ll find it harder and harder to lose weight or to look good naked. In other words, even if you get to an ideal weight, you may find that you’re skinny-fat.

So, what can you do to preserve your muscle tissue? There are two main strategies. One is to lift weights. The other is to get adequate and regular intakes of protein. Every time you ingest quality protein, you’re stimulating some muscle synthesis. If you do that over several feeds a day and consistently for months on end, you’ll lose a lot less muscle. You may even gain muscle if you’re lifting weights.

Some of our personal training clients in Northampton manage to gain muscle and lose fat at the same time. They achieve this by training hard and sticking to the advice to consume moderate amounts of protein regularly. They get the right amount of protein for weight loss and simultaneous muscle growth.

It takes energy to process it

Unlike fat and carbohydrate, protein has a high energy cost. The energy required to break down and digest your protein is around 20% of the calories in the protein. So, for example, if you consume 25g of protein delivering 100 calories, you’ll use 20 calories just processing it.

Of course, using up calories generates heat. For this reason, the energy cost of digesting food is often referred to as the Thermic Effect of Food (TEF). The TEF for protein is 20%, whereas it’s 5% or less for fat and carbohydrate.

So, it makes sense to maintain a higher protein intake. How high? Current recommendations are to consume around 0.8g per kg of body weight as a minimum to meet nutrient requirements. But the acceptable range allows for intakes as high as 35% of calories.

Our recommendation would be to keep protein at around 25% of calories. This will allow you to maximise muscle protein synthesis several times a day. Any more than that will simply be oxidised. In other words, it will be used for energy.

You don’t want that. For a start, you don’t want your body to be good at oxidising protein. After all, your muscles are made of protein. And you want to discourage your body going after your precious muscles when energy is low. Second, if you have too much protein, you leave less room for other macronutrients. Carbohydrate containing foods like fruit and vegetables are far more useful to you, and more health-giving, than additional protein.

You’ll eat until your protein requirements are satisfied

The Protein Leverage Hypothesis (PLH) predicts that humans will eat until their protein requirements are met. In practice, that means if your food choices are low in protein, you’ll have to eat more of them to satisfy your protein requirement.

It’s been suggested that the PLH is an explanation for the obesity epidemic. The rise in obesity has coincided with an increase in the prevalence of ultra-processed foods. These foods tend to be lower in protein and higher in fat and sugar. If your diet contains a lot of these foods, you’re going to end up overeating in an attempt to meet your protein requirements.

Of course, this is not a conscious process. You’re not thinking, ‘I need to eat more because my protein requirement has not been met’. You’re just not getting satisfaction from your food, or you’ve developed a taste for a food that makes it hard to stop eating.

How do you know how much protein you need to meet your requirements? The RDA for protein is 0.8g per kg of bodyweight. That’s the minimum necessary to meet protein requirements. But your particular needs may be higher than this. It’s been suggested that as you get older, your requirement should be higher to combat sarcopenia. Or maybe you’re an athlete who needs to build and maintain muscle. Or perhaps, genetically, you simply have a higher requirement.

But I’d also suggest that our earlier recommendation of 25% of calories from protein is almost certainly higher than your biological need. So, unless you’re finding yourself hungry all the time, you should cap your protein intake at around that level.

Summary

You should prioritise protein for weight loss success. Consume at least 20g of protein with every meal and snack and set your total protein intake at around 25% of calories. You’ll lose weight more easily, be more satisfied by your food and be better able to maintain a healthy weight over the long term.