Does eating fat make you fat? The skinny on fat

A photograph of the whole food ingredeints used to naturally flavour Purition, such as macadamia nuts, coconut, walnuts & pistachio nuts.

Does eating fat make you fat? No, but overeating refined carbs and sugar might. Here’s why eating fat won’t make you fat; and why this super-satiating macronutrient can actually help you to drive a healthy and sustainable weight.

“Purition contains 12g of fat. Won’t this make me gain weight? I just can’t seem to shake my fear of fat.”we're asked this question all the time.

Where does the fat fear come from?

This entrenched fear of fat stems from the diet-heart hypothesis back in the 1950s. Nutrition researchers stated that a diet high in saturated fat raises cholesterol levels, which could then lead to heart disease.

Based on these ideas, dietary guidelines, including the infamous ‘Eatwell’ plate and food pyramid, were developed. They encouraged people to follow a low-fat diet — specifically, reducing their saturated fat consumption — in a bid to lower cholesterol, tackle obesity and reduce rates of heart disease.

What happened? Well, lots of people did indeed cut right back on saturated fats. But instead of filling the gap with healthy unsaturated fats, they ate more sugar-packed, low-fat diet products and highly-processed carbs. They also chose low-fat dairy over natural and nutritious high-fat dairy.

As you’d expect, the end result was — and still is — not favourable for obesity or heart health. Obesity rates have increased. Heart disease numbers have increased. Type-2 diabetes rates have increased, too. Most experts blame these unintended consequences on the increase of sugar, packed, carb-heavy processed foods, and the decrease of healthy fats, in the diet.

In fact, it was in the midst of the low-fat diet craze in 2000 that experts announced the global obesity crisis.

"The change in dietary advice to promote low-fat foods is perhaps the biggest mistake in modern medical history, resulting in devastating consequences for public health. Sadly this unhelpful advice continues to be perpetuated."

Dr Aseem Malhotra

Does eating fat make you fat?

Eating fat, as part of a balanced diet, will not make you fat.

Anyone can become overweight by eating too many calories from any nutrient – whether that be fat, protein or carbohydrates. But still, calories are not created equal.

Healthy fats stabilise your blood sugar, keep you fuller longer, reduce snacking and, in turn, naturally help you to reduce your overall caloric intake. In comparison, carbohydrates and sugar stimulate your appetite and make it harder to control your intake of calories.

That’s why eating more fat and fewer refined carbohydrates – just like you’ll find in Purition – is the best tool for sustainable weight loss.

If you’d like to know more, here are 4 reasons why eating fat will not make you fat and why healthy fats are essential for optimal health.

A photograph of the 7 whole foods used in all Puriton wholefood nutrition recipes; chia seeds, sesame seeds, sunflower kernels, flaxseed, coconut, pumpkin seeds and almonds.

1. Less fat = more sugar & carbs

When you build your diet around fat-free foods, you’ll naturally be replacing hunger-crunching fat with hunger-driving sugar and carbs.

"When fat intake is high, carbohydrate intake is lower, and vice versa."

Precision Nutrition: The Essentials of Sport and Exercise Nutrition

A review of 50 diet studies and weight gain found that, on average, the more refined grains (carbohydrates) someone ate (like bread, rice and pasta), the more weight they gained.

That’s because refined carbs and sugar encourage overeating, whereas fat makes you feel full. Low-fat, high-carb diets make you feel hungry, while high-fat, low-carb diets make you feel satisfied.

"The last four decades of data tell the same story. We were told to avoid eating fat, so we reduced our relative intake of fat, increased our intake of starches and sweets, increased our total caloric intake, and ended up heaver and diabetic as a result."

Jonathon Bailor: The Smarter Science of Slim

2. Fat stabilises insulin

Insulin is like the body’s energy controller. When you eat something, your body releases glucose (energy) into your bloodstream. This triggers insulin production, a hormone that regulates your blood glucose levels by sending the glucose to the right place. Insulin will send this energy to be burned for energy or to be stored, as body fat, for later.

If you eat a high-carb meal (as is often the case with low-fat dieters), your blood glucose levels spike massively. You’re unlikely to need all of the incoming glucose for energy, so insulin sends a large portion to be stored as body fat for later use. 

"The low fat/high carbohydrate diet we’ve been told to eat for 40 years has raised insulin levels, triggering fats cells to hoard too many calories. As a result, there are too few calories in the bloodstream and available to fuel the needs of the rest of the body. Our brain recognizes this problem and takes measures to save energy – so we get hungry, metabolism slows down, and we gain weight."

Dr David Unwin: Always Hungry? 

In comparison, eating plenty of fat (and fewer carbohydrates) stabilises insulin. Fat digests much slower—typically around four to six hours—resulting in a slower release of glucose. Hence, your insulin levels are not overstimulated, which helps to prevent the unwanted storage of body fat.

In short, a low-fat, high-carb diet actually stimulates fat production and storage (via insulin), rather than prevent it.

3. Eating fat reduces your appetite

Fats are last to leave the digestive tract, which makes you feel fuller for longer.

But fat’s satiating power is also because of the effect it has upon your hormones. Eating fat activates leptin, a hormone that sends a signal to the brain to say that you have received enough fat to nourish your cells. This reduces your appetite.

And the science backs it up. Studies on fat and satiety have found that healthy unsaturated fats have a positive effect on satiety and help to regulate your appetite by regulating the release of appetite-reducing hormones.

"Full-fat foods tend to be more nutritious and satiating, while sugar has no nutritional value and actually promotes fat storage."

Dr Aseem Malhotra - Follow him on Twitter

But that’s not all. When you eat a high-carb, low-fat meal, your blood sugar levels spike rapidly. The problem? The quicker they rise, the quicker they fall, which leads to an intense feeling of hunger, lethargy and annoying sugar cravings.

In comparison, eating a meal rich in protein, fibrous carbs and healthy fats will take longer to break down in the digestive system, which prevents blood sugar peaks and hunger-inducing dips.

So much so, that when a study compared changes in appetite on a low-carb vs low-fat diet, the low-carb group was were significantly less bothered by hunger compared to the low-fat group.

4. Fats are essential for optimal health

Weight loss and appetite aside, fat is essential for good health.

Your body needs essential fatty acids to support its basic functions. Your body can’t make them on its own, which means you have to consume them through dietary fat.

Fat also:

  • Provides an energy source
  • Helps to balance hormones
  • Forms your brain and nervous system
  • Transports essential fat-soluble nutrients

"A balance of dietary fat with a mixed intake of saturated, monounsaturated and polyunsaturated fats is critical for optimal health and function."

Precision Nutrition: The Essentials of Sport and Exercise Nutrition

And there’s more! Eating plenty of healthy fats is correlated with numerous long-term health benefits, such as reduced risk of heart disease and inflammation, which can help to prevent chronic disease.

Find out more about essential fats in our omega 3 guide.

Knowing your fats

We know by now that eating fat won’t make you fat. In reality, it can actually help you to feel your best and lose weight, without feeling deprived.

But fats aren’t created equal, and as you begin to include more fat in your diet, it’s important to focus on the right kinds.

From top to bottom - horizontal stripes of sunflower kernels, almonds, chia seeds, pumpkin seeds, coconut, flaxseed and sesame seeds.

Unsaturated fats (eat plenty)

Healthy unsaturated fats include polyunsaturated (including omega 3 fats) and monounsaturated fats, which are known for their beneficial effects on cholesterol, inflammation and metabolism.

Monounsaturated fats

  • Olive, canola, peanut & sunflower oils
  • Avocadoes
  • Nut butter
  • Pumpkin & sesame seeds
  • Most nuts 
  • Some animal fats 

Polyunsaturated fats

  • Oily fish
  • Sunflower & soybean oils
  • Walnuts
  • Pine nuts
  • Chia seeds & flax
  • Sesame, sunflower & pumpkin seeds

Saturated fats (moderate)

Saturated fat is traditionally linked to increased blood cholesterol levels and heart disease risk, but more recent studies have caste doubt on these claims. In fact, a 2016 study discovered that people who eat lots of saturated fat do not experience more heart disease than those who eat less.

In addition, unprocessed sources of saturated fat, such as good quality meat and full-fat dairy products, are very nutritious. The solution? Enjoy unprocessed sources of saturated fat in moderation, but limit saturated fats from processed foods like cakes and processed meat when possible.

  • Milk & cheese
  • Fatty beef, lamb & pork 
  • Poultry with skin on
  •  Butter
  •  Ghee
  •  Lard
  •  Coconut oil

Trans fats (avoid)

Trans fats are linked to high cholesterol and a higher risk of inflammation in the body, which can increase your risk factors for heart disease, stroke and diabetes.

The good news? Trans fats are very rarely included in UK-made foods, as most supermarkets signed up to a voluntary agreement not to use artificial trans fats in their products back in 2012.

Just double-check the ingredients list – if a product contains partially hydrogenated oils, it contains trans fats.

Potential sources of trans fats

  • Margarine
  • Fried foods
  • Vegetable shortening
  •  Highly processed foods
  •  Snack foods

Note that these kinds of foods will not always contain trans fats.

Enjoy healthy fats in Purition

If you’re looking to lose weight or improve your diet without feeling hungry or deprived, try Purition.

Our wholefood blends deliver quick, convenient nutrition from 100% whole food ingredients with a balanced combination of protein, healthy fats and fibre to leave you feeling energised and full for 4–5 hours.

We’ve packed freshly ground almonds, pumpkin seeds, coconut, whole chia seeds, sesame seeds and golden linseeds into every bag to give your body the healthy whole food fats and essential fatty acids it needs to thrive.

Alongside our core blend of nuts and seeds, Purition contains triple-filtered whey or plant protein, as well as extra gut-healthy fibre from wholefood sources.

Photograph of Purition served 4 ways; instant oat free porridge, meal shake, energy balls, layered yoghurt bowl.


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