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Low-carb or low-fat: Which is best for muscle definition?


Successful muscle definition isn’t the result of luck or magic, but rather the culmination of hard-work and dedication to training and nutrition. Training alone will not result in muscle definition so it's important to keep your diet in check. 

But what is the right diet?

There are numerous contradictory arguments surrounding diet plans, but one discussion that’s at the forefront is whether a low-fat diet is more beneficial than a low-carb one. To add to the confusion, a 2015 study conducted by the US National Institutes of Health found that while a low-fat diet loss led to more fat loss, a low-carb diet led to more weight loss overall.

The conditions of the study were extremely niche however, putting patients through an extreme low-carb low-fat diet plan to achieve the results. This makes the process less relevant to most people’s everyday lifestyles, but nonetheless it raises an important notion – the best diet is the one that you stick to.

Choosing the right diet plan to get lean

The most important thing for any diet is to maintain the right number of calories, which will be vary from person to person. If you’re looking to lose fat and increase muscle definition, then you need to be in an appropriate calorie deficit to help you reduce fat at a healthy rate. The NHS has a recommended weight loss plan which is designed help you reduce weight at a safe rate of 0.5kg to 1kg (1lb to 2lb) each week.

If you want to track your calories, there are a number of free online calorie calculators available to get a rough estimate of how many calories to consume each day which is a good starting point. You can then use this number to guide you with how many calories to eat by tracking this using a calorie counter, such as MyFitnessPal, and see how you feel and how your body responds with this intake. You will probably find you will need to adjust your calories over time.


If you’re opting for a low-fat diet plan to increase muscle definition, then you should add plenty of protein-rich foods to your regime. Create balanced meals by combining plenty of vegetables with protein, using low-fat foods such as:

  • Chicken
  • Beef
  • Fish
  • Eggs
  • Dairy products

Avoid limiting fats completely as these are essential for a healthy body function. Opt to eat fats from wholefood sources such as olive oil, fish and nuts.


If you’re thinking of getting lean on a low-carb diet, try to get your carbohydrate sources from wholefoods and limit the amount of processed carbs you eat. Eliminating carbohydrates from your diet completely is not recommended or neither healthy.

You’ll want to ensure you get a balance of proteins, carbs, and fats. Consider the following:

  • Proteins: eggs, beef, chicken, cheese, fish
  • Fats: nuts, fish oils, coconut oil
  • Carbs: oats, rice, sweet potatoes, fruit, vegetables

Can you live without carbs?

Carbohydrates provide you with the fuel you need to lift weights and build muscle. Healthy carbs, such as high fibre starchy foods, vegetables, and fruits are also an important source of nutrients, including calcium, iron, and vitamin B.

If you were to significantly reduce carbs from your diet in the long term, you could be at risk of seriously depleting your body’s nutrients, which can lead to several health issues.  It’s important to maintain the right balance of carbs in your diet, as they can help in a number of useful ways, including:

  • Increasing energy levels
  • Reducing the risk of disease and infection
  • Monitoring your calorie intake


Whether you opt for a more low-fat or low-carb diet, the importance of having a balanced diet cannot be underestimated. While you might want to try to limit the amount of fatty foods and carbohydrates you have, it's important to have a good mix of good proteins, fats, and carbs. In order to achieve fat loss and see muscle definition a combination of weight training and and being in an appropriate calorie deficit if recommended. Eliminating whole food groups can elicit fat loss through restricting your food choices but this will not be sustainable or healthy in the long term.


If you’re looking to build muscle and improve your health, start your fitness journey today and check our Gyms in London or find a gym near you.

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