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Why is it important to understand your body composition?

Why appearance and body weight alone aren’t reliable indicators of a reasonable body fat percentage.

Why Is it Important To Understand Your Body Composition? | Juniper

At first glance, the term ‘skinny fat’ might appear to make little sense. After all, the 2 words are totally at odds with one another. 

However, the term is used widely to describe someone who seems slim but is actually storing a high amount of body fat. 

Their weight is considered in the healthy range according to their body mass index, although their body composition tells a very different story. 

This is why appearance and body weight alone aren’t reliable indicators of a reasonable body fat percentage. Instead, it’s crucial to understand your body composition to work out whether you’re carrying an ideal amount of internal body fat. Here’s everything you need to know about the skinny fat body type and why body composition is fundamental to healthy weight loss.

What does a 'skinny fat' body type mean?

A skinny fat body type is one that looks lean from the outside but has high body fat and low muscle mass on the inside. Skinny fat people may have a ‘normal’ body mass index (BMI), however, this isn’t always a sound way of gauging healthy fat levels. 

BMI looks at weight and height, not your overall body composition — so things like body fat percentage, muscle mass and skeletal mass. Instead, some consider lean body mass (your overall weight minus your body fat weight) to be a better measure of health. 

Note that ‘skinny fat’ is not an official medical term. However, it’s used pretty frequently in fitness and nutrition to describe this particular body type. 

You might also hear it referred to as ‘metabolically obese normal weight’ (MONW), which is where someone is in the normal weight range but has the markers of obesity like excess body fat, impaired insulin sensitivity, and a higher likelihood of diabetes, cardiovascular disease and death [1].

What are the signs of a 'skinny fat' body?

There are a few tell-tale signs when it comes to being skinny fat [2]. Someone might appear to be slim and reveal a healthy weight on the scales, but their body could be hiding any or all of the following:

Other things that can indicate a skinny fat body include eating a poor diet and not putting on weight, and not doing enough exercise. Someone who’s skinny fat may also feel exhausted or out of breath after only a brief amount of exercise.

Why do people gain fat and lose muscle?

Interestingly, high body fat percentage and low muscle mass are heavily intertwined. This is because weight gain and muscle loss tend to happen concurrently [4]. 

A lot of the time, this is due to age-related muscle loss and reduction in metabolic rate. In other words, you lose muscle and your metabolism naturally slows down as you get older. These factors mean your body can have a higher fat percentage and lower muscle mass over time. 

Other things can exacerbate this change in body composition, including losing weight purely through diet. In a healthy weight loss programme, your body should use fat for energy before muscle. But if you’re not eating, heavily restricting calories, cutting a particular food group or staying in a calorie deficit for too long, the opposite can happen. 

The same goes if you don’t incorporate any resistance training (also known as weight training or strength training) into your exercise routine. But more on this shortly.

What causes someone to become 'skinny fat'?

There are several reasons why someone might become skinny fat, from lifestyle to genetic factors.

Genetic predisposition

How much fat your body retains and where your body stores fat are largely determined by genes [5]. So, if you have an immediate family member with a skinny fat body type, there’s a higher chance you’ll have one too.

Lifestyle habits

Someone who’s skinny fat will often have a diet high in processed foods, sugar and refined carbohydrates, but low in whole foods, fibre and protein. On top of that, they may not be doing enough — or any — exercise. Alternatively, they might only be focusing only on cardio and avoiding weight-bearing exercises. Only doing cardio can contribute to muscle loss [4]. On the other hand, resistance training is essential for muscle growth.

Hormonal imbalance

In some cases, hormonal imbalances can lead to excess fat, particularly around the midsection. The different hormonal imbalances and conditions linked with belly fat include low oestrogen (often a result of menopause), hypothyroidism (an underactive thyroid), insulin resistance, elevated cortisol (due to ongoing stress) and leptin imbalance.

Prolonged calorie deficit

A calorie deficit is when you use more energy than you consume, which is the basic premise of weight loss. But if you stay in a state of calorie deficit for a long time — that is, beyond reaching your target body weight — your body can actually start to eat away at your muscles [6]. 

As a result, your body may store more fat and less muscle, leading to a skinny fat physique.

Are there any dangers of being 'skinny fat'?

Unfortunately, anyone with excess body fat — particularly around their mid-section — is at risk of certain health issues. Your body contains 2 types of fat: subcutaneous fat (the fat you can see and feel) and visceral fat. Often, those with a skinny fat body carry a high amount of visceral fat — i.e. the kind you definitely don’t want. 

Visceral fat is hidden fat that sits around the belly, surrounding your organs. It's one of the main signs of metabolic syndrome, a term used to describe disorders like obesity, high blood pressure, high cholesterol and insulin resistance. 

Metabolic syndrome also raises your risk of cardiovascular problems, stroke and type 2 diabetes [3]. 

Excess visceral fat is linked to other conditions too, including breast and other types of cancer, liver disease, dementia, fertility issues and osteoarthritis [7].

Who’s at risk of being ‘skinny fat’?

  • The people most at risk of becoming skinny fat, or MONW, are those who are lean but have the metabolic profile of someone who’s overweight. There are a number of things that make a person predisposed to becoming skinny fat, including:
  • Maintaining an unhealthy diet
  • Doing a low amount of (or no) physical activity, particularly weight training
  • Having impaired insulin sensitivity
  • Having high blood pressure
  • Having high triglyceride levels (this is a type of fat found in the blood)
  • Having high LDL cholesterol and/or low HDL cholesterol (in other words, too much of the ‘bad’ type and not enough of the ‘good’ type)
  • Having immediate family members with a skinny fat body type.

How to overcome being 'skinny fat'

Even if your body is showing the signs of being skinny fat, you can definitely turn things around. Here’s how to reduce body fat and build and maintain muscle the right way.

Add weight training to your routine

The benefits of aerobic exercise, or cardio, for your overall health can’t be underestimated. It reduces the risk of heart disease, offers mental health benefits, and can help manage other conditions including diabetes [8]. 

However, if your exercise routine only contains cardio, you may not be doing enough to build muscle and maintain adequate muscle mass. The UK Government’s physical activity guidelines recommend doing resistance training at least 2 days a week [9]. 

Not only will this help create the muscle needed to overcome a skinny fat body, but it will also improve bone density, the function of your joints and overall strength [10].

You can easily incorporate resistance training into your routine by lifting weights and doing squats, push-ups and any other exercises that put your muscles to work.

Maintain a balanced diet

Eating healthily is another pillar of sustainable weight loss. 

Protein should be a fundamental part of your diet, as it’s needed to build muscle. Animal-based protein sources like meat, eggs and dairy tend to be absorbed better. However, plant-based sources like tofu, legumes, nuts and seeds are still valuable [11].

Ensure you’re eating lots of other nutritious foods too, like whole grains, fruits, vegetables and healthy fats. Wherever possible, avoid foods high in salt, sugar, energy and saturated fat [12].

Lose body fat slowly

Healthy, sustained weight loss isn’t about skipping meals, cutting out a particular food group or reducing energy intake to a dangerously low level. 

Experts generally agree that a weight loss rate of about 1-2 pounds per week is safest [13]. Anything that promises drastic results in a short period of time can have negative consequences on your body, including muscle depletion, rapid weight gain following the initial loss, and a slowing of your metabolism [14].

To lose weight safely, aim for 30 minutes of exercise on most days combined with a reduction in energy intake of 500 calories, or about 2000 kilojoules. And unless you’ve got direction from a healthcare professional, your energy intake shouldn’t drop below 1200 calories (5000kj) per day if you’re a woman [13].

Address any underlying issues

If you think your skinny fat body might be due to a hormonal imbalance, make an appointment with a healthcare professional to address it. Your doctor can check for conditions like hypothyroidism, liver problems, chronic stress and oestrogen imbalance by looking at your hormone levels.

Tackling these through medication and other treatments, like hormone replacement therapy, may contribute to combatting a skinny fat body.

Consider a programme to lose weight

Sometimes, it helps to have dedicated resources and support throughout your weight loss journey.

Juniper’s Weight Reset Programme combines proven weight loss medication, health coaching and ongoing support to help you lose weight and keep it off. We prescribe a GLP-1 medication called Wegovy, which contains the active ingredient semaglutide.

Semaglutide is clinically proven to reduce your appetite and make you feel fuller for longer, while also reducing cravings by targeting the rewards centre in the brain. 

For long-term success, changing your eating and movement habits is also crucial, which is why we offer a comprehensive programme that includes 3 core pillars of lifestyle change with the assistance of our UK clinicians.

We can help you break habits that might be impacting your weight and help you hit your weight loss goals sooner.

Is body recomposition the right solution to lose fat?

Body recomposition — where you aim to lose body fat and gain muscle — is a great option for sustained, safe and long-term weight loss. Building muscle supports metabolic function, overall strength, improved bone density and more. 

However, altering your body composition does require a lot of dedication and the right balance of exercises and dietary changes. This is why engaging a healthcare or weight loss professional to help you lose weight can be beneficial. They can ensure you’re achieving your weight loss goals and combatting a skinny fat body in a sustainable and healthy way.

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