Looking to lose fat and build lean muscle? A dietician's cheat sheet, plus why eating enough protein is key

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You'll likely know by now that protein is a pretty essential macronutrient. Not only does it keep you satiated and help your muscles to repair, but it also helps your muscles to grow, making it a gym-goers favourite.

But did you know that protein can also be key for fat loss? Likely not, as it's long been drilled into us that the only way to lose weight is by monitoring your calories.

One important thing to point out here - at Marie Claire UK, we firmly believe that you should never feel the need to lose weight or change your body. Life is about so much more than how you look, and your worth will never be defined by a number on a scale. That said, if you're aesthetically motivated and feel you'd like to try a new routine - and are confident that you can do so from a mindful and positive place - then we're here to arm you with the right facts (aka what works and what, well, doesn't).

For a more thorough understanding of how protein can impact your body, plus how to consume enough of it, we spoke to Juniper dietician Amelia Bandera. Don't miss our guides to the best protein powders and vegan protein sources, plus a nutritionist's guide to how much protein you need per day.

How to eat enough protein in a calorie deficit, according to a dietician

Why is protein important?

Good question. "Protein is made up of amino acids, which are the building blocks of muscle," sports nutritionist Abi Roberts previously shared with MC UK. "Our bodies use amino acids to repair and rebuild muscle tissue that's broken down during exercise or daily activities. This process is called muscle protein synthesis."

So, why is this important when it comes to knowing what to eat? "Breaking down the muscle and repairing it with sufficient amino acids promotes muscle growth. Additionally, protein can also help with muscle recovery after exercise, reduce muscle soreness, and improve overall muscle function," she continues.

And how is protein important if your goal is fat loss? Well, according to Bandera, it helps to reduce cravings by promoting feelings of fullness. “Protein is known to be more satiating than carbohydrates or fats, making it a key component of each meal and snack," the expert explains. "Eating protein-rich foods can help you feel fuller more quickly and for longer, which can help reduce overall calories to support a calorie deficit,” she tells Marie Claire UK.

Secondly, the nutrient is essential for maintaining and building lean muscle mass, which not only makes you look more toned, but can contribute to a higher resting metabolic rate, helping you burn more calories at rest. “On any fat loss journey, there’s a risk of losing both fat and muscle,” she explains. “Ideally, you want to preserve as much muscle as you can when losing fat, as muscle is more metabolically active than fat, meaning muscle tissue helps our body burn more energy, which will also help to maintain weight loss success.”

How to get enough protein in a calorie deficit

Bandera shares three key tips.

1. Aim for 30 grams of lean protein with each meal

“Protein helps keep you feel fuller more quickly and keeps you satisfied for longer after your meals. Eating a good source of protein with each meal ensures that you’ll feel satisfied until your next meal or snack," shares the dietician. This, in turn, "can help with portion control and staying in a calorie deficit.”

2. Prioritise eating your protein source first at each meal

"As protein helps you feel satisfied more quickly, prioritising the protein in each meal can help with managing portion sizes of your meals," she goes on.

3. Choose lean protein sources over processed ones

“Lean proteins like chicken breast, fish, tofu, eggs, beans and legumes, and lean red meat will be lower in calories and higher in protein than processed meats like sausages, salami, prosciutto and ham," explains the expert.

What are the best high protein foods for fat loss?

Because not every protein is created equal (and by this, we mean some high sugar, highly processed protein shakes may not be the best option for daily consumption, despite helping you to hit your daily protein target).

1. Animal sources

“Lean sources of animal proteins are good choices for both healthy eating and sustained weight loss," shares Bandera.

Try this: Grilling, baking or poaching your meat is a great way to keep the overall calories of the meal low, Bandera explains.

Some examples of lean protein sources include:

  • Chicken breast
  • Fish
  • Beef
  • Cottage cheese
  • Greek yoghurt
  • Skyr
  • Eggs.

2. Plant-based sources

“Plant-based proteins such as beans and legumes are beneficial for your heart health," explains the dietician. "Even if you don’t follow a plant-based diet, including plant-based proteins in your diet is a great way to get a variety of proteins and other nutrients."

Her go-to plant-based proteins include:

  • Beans
  • Legumes
  • Tempeh
  • Tofu
  • Seeds
  • Nuts
  • Yoghurt
  • Soy-based milk.

3. Grains

"Including high-protein grains can be a great way to boost protein of a meal, particularly if you’re following a plant-based diet," continues the dietician.

Looking for a high-protein side to go with your tofu, beef or chicken? Bandera recommends:

  • Quinoa,
  • Freekeh
  • High-protein bread
  • Farro.
Ally Head
Senior Health, Sustainability and Relationships Editor

Ally Head is Marie Claire UK's Senior Health, Sustainability, and Relationships Editor, nine-time marathoner, and Boston Qualifying runner. Day-to-day, she works across site strategy, features, and e-commerce, reporting on the latest health updates, writing the must-read health and wellness content, and rounding up the genuinely sustainable and squat-proof gym leggings worth *adding to basket*. She's won a BSME for her sustainability work, regularly hosts panels and presents for events like the Sustainability Awards, and is a stickler for a strong stat, too, seeing over nine million total impressions on the January 2023 Wellness Issue she oversaw. Follow Ally on Instagram for more or get in touch.