‘Skinny genes’ and the influence of diet

Do skinny genes really exist and can we overcome genetics?

Qualified Nutritionist (BSc, MSc, RNutr)
Ask Emma

10 December 2018

Are ‘skinny genes’ a thing?

Over the years, various research trials have been conducted in order to help determine if there are really ‘skinny genes’. Why do some people really struggle with their weight whereas others seem to eat what they want without putting on any extra weight? Whilst diet and lifestyle are the obvious contributing factors, weight differences in animals have given us reason to believe there may be more to it than that; and perhaps there’s also more of an internal driving factor - genes.

Over the years, up to 50 difference genes have been discovered which are indeed thought to have an influence on our weight and body composition. Many of these are assumed to influence how we absorb and metabolise fats, and even have an influence over our appetite. 

One of the most recent discoveries was the ‘skinny gene’ which has been so-called ‘adipose’1. This was originally discovered in fruit flies, but has also been found in rodents and humans.  If the gene is switched on, the individual is more likely to be ‘skinny’, whereas if it’s switched off, we’re more likely to store more fat, or adipose tissue. However, interestingly the ‘skinny gene’ isn’t thought to be simply switched on or off, but may be switched on to varying degrees in different people1.

The role of gut bacteria

As well as inherent genes having an influence on our body weight, there are potentially other internal influences too, such as the balance of bacteria in our gut. 

Gut bacteria trials have shown that the prevalence of certain types of bacteria are linked to different body weights between people2, and although it’s not well understood how exactly this works, we know that these bacteria can release chemicals which can potentially alter our genes too3

Although gut bacteria can be influenced from birth (with caesarean born babies found to have a different balance from those born naturally), there are plenty of steps you can take in terms of your diet and lifestyle to help promote a healthier balance of gut bacteria and, therefore, potentially influence your weight this way too – another important consideration!

The influence of diet

Although people are becoming more interested in genetics and what genes we may or not have – the reality is you’re stuck with your genetic makeup. However, what I really want to stress is that you can influence these genes in a number of ways:

1 - The power of nutrition could switch genes on or off

We know that diet and our environment can influence our genes directly. Interestingly the ‘skinny gene’ is thought to be switched on to different degrees in different people – so everyone has it, we just need to influence it.

2 - Genetic factors aren’t the be all and end all

Although certain people may be pre-disposed to certain things as a result of their genes, when it comes to body weight (and lots of other factors such as disease states), there are lots of reason to believe that we can overcome even genes, as a result of external influences such as diet and lifestyle, at least to a certain extent! For the vast majority of people, managing their diet or working on more exercise will have the desirable effect when done in the right way.

3 - Genes alone aren’t to blame for the recent increase in obesity 

Only blaming our genes risks being a bit of a cop out when it comes to body weight. As both obesity and the associated diseases such as diabetes have increased exponentially in all parts of the world over a similar time frame in recent years, we know that genes aren’t the whole story. This trend suggests diet, eating habits and social influences are much more likely to be playing the main role.

Are there specific diets that can influence our ‘skinny genes’?

There seems to be a constant flow of new fad diets available nowadays and it can be difficult to know which, if any of them, are likely to be suitable for supporting your health or specific weight loss goals.

In terms of potentially influencing those ‘skinny genes’ the Sirtfood Diet has been given some special attention recently. The Sirtfood Diet is so-called because it is rich in foods high in special chemical compounds called sirtuin activators. Sirtuins are a specific class of enzymes which are thought to have beneficial effects in the body and the foods they can be found in include lots of healthy items such as green tea, dark chocolate, citrus fruits, apples, turmeric, blueberries, kale and red wine. 

Now, although I’m all for including these foods in your diet, it has to be said, the research is a little sketchy in terms of the specific effects that these foods can have, as a result of their sirtuin activator content. The Sirtfood Diet guidelines are generally pretty controlled, fairly strict with little room for leeway, they involve cutting calories quite dramatically and replacing proper meals for juices. Although these kinds of plans can in some cases be helpful in the short-term for example, as part of a gentle detox, longer-term it’s unlikely to be so sustainable. It’s much more realistic to adopt a lifestyle which supports your health and body weight in the long-term. 

Summing up & taking action

So, if you’re desperate to take action and support a healthier you, skinny genes or not, here’s my advice:

1 – Incorporate the Sirtfood diet components into your regime anyway

Rather than following a super strict regime and prescriptive recipes, why not just make an effort to include more of the components of the Sirtfood diet in your regime anyway? Whether or not the sirtuins are having specific actions in the body, these foods are packed full of vitamins, minerals and antioxidants which are important for supporting healthy bodily processes and a buzzing metabolism.

I genuinely believe that cooking from fresh is the key to a healthy body weight. It’s all the processed foods with hidden sugars, salts, fat (and the rest!) that are much more likely to contribute to us piling on the pounds. Eat fresh, get into the habit of planning and cooking your meals and you’ll soon feel and notice the difference.

2 – Don’t forget about the healthy fats

Something that the Sirtfood diet is arguably lacking is a good dose of healthy fats. People are often in the habit of avoiding fats, especially when trying to lost weight, but believe it or not we need healthy fats to support our metabolism and stay lean! Read my blog on this topic for more info. 

A recent study also highlighted this idea nicely and found that elderly people who actively introduced an additional 300 calories per day from walnuts had no negative effects on body weight or body composition which includes fat distribution. This is really promising, and just think of the possibilities if you included these and cut out something less helpful instead! So no excuses, get incorporating those fats!

3 – Regardless of your genes, take control of your lifestyle

Even the experts have agreed that there’s almost nothing you can’t do to influence your genes. So even if we are predisposed to certain body types or disease states, it only means we are at a greater risk of these different states, it isn’t inevitable that we’ll become affected. Therefore our diet, daily habits and lifestyle factors can all have an influence and even small changes could potentially make the world of difference.

One top tip to consider is how much water you drink. We know that water influences every system of our body, and research has suggested that this simple constituent of our diet could be crucial for supporting our genes and overall health4

Not only are the benefits of water there, but if you drink more water you’re less likely to drink other things – other potentially more harmful things. There’s been a steady increase in the consumption of calorific drinks in recent times, and with calories come all the sugar, artificial sweeteners, caffeine and alcohol which are common components of drinks that aren’t water – all of which aren’t likely to do your metabolism any favours! So, drink up, and add a slice of lemon or some other fruit if you’re struggling initially

4 – Herbal helpers 

If you’re struggling to lose weight, although there’s not likely to be any quick fix in terms of products (yes people, diet and lifestyle really is key!) there are a few areas you could concentrate on to help aid your progress:

Support your metabolism with Kelp

Supporting your thyroid gland and metabolism is always an important consideration if you’re working on your weight. Especially in the approach to menopause, or if your hormones have been playing up recently, your thyroid might need some gentle support and our Kelp tablets with a sensible dose of iodine can be a welcome addition!

Support your stomach with bitter herbs 

Supporting your stomach with some bitter herbs such as Yarrow helps ensure that you are absorbing all the essential nutrients from your food and making the most of them. Magnesium helps support insulin sensitivity and B vitamins help us to convert our food into energy – these are just two nutrients worth mentioning which are super important for supporting a healthy body weight. 

Support your gut with prebiotics

In order for the bacteria in your gut to survive and do their job sufficiently (metabolism is a big part of this), they need to be in a suitable environment. Adding a good dose of L+ lactic acid to you daily regime by using Molkosan can help create just that, and you’ll definitely want to do this first before considering introducing any probiotics supplements.


1. https://www.sciencedaily.com/releases/2007/09/070904122434.htm

2. https://europepmc.org/abstract/med/29409054

3. https://www.mdpi.com/2072-6643/10/9/1317

4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2908954/


Kelp tablets

240 tabs

£ 7.99

Buy now

Kelp tablets from Pacific sea kelp. To help maintain normal thyroid function in the body.
More info

Molkosan® Original – A prebiotic for good gut bacteria


£ 6.25

Buy now

Prebiotic whey drink, rich in L+ lactic acid, for good digestion. Also available in 500ml size.
More info

Video: Fermented Tomato Ketchup

Ready to try something new? Watch Emma's recipe video for a delicious Fermented Tomato Ketchup!

Get the recipe

What are superfoods?

You've probably heard all the fuss about superfoods, but what does this mean, and what foods count as superfoods?

Find out now

How much fruit & veg do you need?

Is 10 portions of fruit and vegetables daily really achievable? Our nutritionist Emma Thornton tells us her thoughts.

Learn more

Kick it up a notch!

Our Herbamare combines herbs and vegetables with a little sea salt to create a delicious, healthy seasoning for any dish!

Find out more

Healthy & nutritious dinner ideas

Get new recipes in your inbox every week. Sign up now

New! Passiflora Tablets & Spray - Learn more