Try us for free for 7 days - LIMITED OFFER

The Skinny on Fat - Part II

Rachel Lett, RNutr

Chief Care Officer


The low-fat diet has tainted our health and mind-set—unfortunately most adults are innately ‘fat phobic’. In the two part series, ‘The Skinny on Fat”, I want to help you overcome ‘fat phobia’, so that you can get your health back on track, and even reverse diabetes 💪

Rather than advise you, as a Nutritionist, to eat more fat. I want to equip you with information so that you can make up your own mind.

Last week I spoke about the origins of the low-fat diet, and how it is based on weak evidence and mass propaganda. If you haven’t already had a look, take a peak now.

In part two of the series, I want to describe the functions of fat, so that you will understand why it is necessary to eat enough of it — our bodies depend on it.

Before we begin, do a little body scan and check how you’re feeling. Have you got low energy, not able to deal with stress, mood disorder, blurred vision dry- flaky skin, brittle nails, foggy brain, poor concentration or memory loss? Have any of these symptoms resonated with you?

If so, your body could be letting you know that you’re deficient in fat. Keep this in mind while you read how integral fats are for our daily life and functioning.

Function of fats

1. Integral for cell membrane structure.

This is a big one. In essence, fat molecules are essential for life 💓. They make up the cell membrane structure and regulate the internal workings of the cell. The cell membrane acts as a bodyguard🛡 for the cell— it protects from the outside environment and controls the movement of molecules in and out from the cell.

The cell membrane is primarily composed of phospholipids (made up with saturated and unsaturated fatty acids), cholesterol and proteins. The phospholipid, bonded with cholesterol is a clever creation making the cell membrane both solid and fluid, allowing molecules to pass in and out of the cell.

As you can imagine, without sufficient fat and cholesterol, cell membranes lack strength, structure and function. Unable to communicate and regulate molecules in and out of the cell, the cell becomes weakened and susceptible to disease 🤕.

Within the cell, reside the mitochondria — specialised structures that generate ATP, the main energy source for the body. The mitochondria have a similar membrane to that of the cell. Likewise, they require fatty acids and cholesterol for stability and function.

Fundamentally, the health of the cell is directly related to the availability of fatty acids and cholesterol. If you restrict these nutrients, you will have less energy and be more vulnerable to disease. So next time you reach for that 0% fat-free yoghurt, think about your hard working cells!🤔

2. Promotes brain functioning 🧠

Believe it or not, we’ve all got fat heads. Our brain is composed of 60% fat and home to 25% of the body’s cholesterol. This statement alone would be enough to suggest why fat phobia has resulted in a spiralling number of Alzheimer's, dementia, ADHD, depression and bi-polar disorder.

Brain fat is used for structure, rather than storage. Fat and cholesterol form a fatty sheath called myelin. Myelin insulates brain cells so that electrical impulses can fire to and from the brain. Similar to other cells of the body, brain cells are enclosed by a fatty membrane, composed of phospholipids and cholesterol. This regulates cell activity and protects it from the environment.

As you can imagine, if we don’t maintain the structure and integrity of our brain, it’ll just start falling apart.

So don’t spend another second thinking about it, get some dietary fat to hotwire your brain cells and keep them in tip top shape!

3. Supports organ function

The fat surrounding vital organs like the kidney, heart and liver is hard and highly saturated. It acts like a protective cushion, preventing injury, and also provides essential nourishment for organ function.

Not to mention, the insulation it provides during the winter months —I know I’d be lost without my fatty winter coat!

With that said, if there is too little or too much fat surrounding the organs, they will not work to their full capacity.

It’s important to limit weight gain around the mid-section, while eating a fat rich diet that supports organ function.

Let’s also look at the lungs. Normal lung function depends on an oily substance called lung surfactant. It removes microbes or debris, and also prevents alveoli (tiny sacs within the lungs) from collapsing when we exhale. Surfactant is composed of phospholipids (fatty acids joined to a phosphate group). Thus, healthy lungs depend on fat.

4. Synthesises hormones

Cholesterol, which is made from saturated fat, is the backbone to steroid hormones. These are glucocorticoids, which help us respond to stress; mineralocorticoids, that regulate blood pressure through the kidneys; and the sex hormones progestogens, androgens, and estrogens, which are responsible for puberty and fertility.

It comes as no surprise that when men and women eat more healthy fats, their fertility often improves and finally partners conceive. 👪

5. Aids absorption of fat-soluble vitamins

As the name suggests, fat-soluble vitamins, including A, D, E and K require fat to be absorb. Once these vitamins have been absorbed with a helping hand from dietary fat, they can be used or stored in fatty tissue for later use.

Vitamin A is vitally important for growth and repair of body tissue; maintaining strong bones and teeth; maintaining healthy mucous membranes in the nose, mouth, throat and lungs; moisturises the skin; helps digest proteins, normal reproduction in male and females, maintaining eyesight 👀 and improving immunity.

Vitamin A has even shown to have therapeutic action in type 2 diabetes, preventing degeneration of eyesight, kidneys and healing.

With such a bounty of health properties, it would be a shame to miss out on this nutrient!

Vitamin D is renowned for bone health — important for the absorption of calcium, which prevents rickets and osteoporosis. Additionally, it has got a lot of attention recently for improving immunity, improving mental health and reducing the risk of heart disease, cancer and diabetes.

In the northern hemisphere, we are graced with dark days and little sunlight (vitamin D), so it’s important to keep our levels topped up through diet!

Vitamin E acts as an antioxidant, protecting cells from damage. This prevents age related conditions and keeps your skin looking flawless! Vitamin E also plays a key role in boosting immunity, keeping colds and flu at bay.

Vitamin K is responsible for blood clotting, protecting against tooth decay 🦷, and directing calcium into the bones, which supports strong bones and prevents calcification (hardening of the arteries) associated with heart disease.

As you can see, without fat, you’re susceptible to nutrient deficiencies despite eating plenty of vegetables.

Get some bang for your buck, and include plenty of fat in your diet to make the most of what’s available!

6. Stabilises blood sugar levels

Fat slows the absorption of sugar into the bloodstream, and thus reduces insulin spikes. When sugar levels are stabilised, energy and mood remain constant. Avoid that mid-afternoon slump 😴, and reduce your risk of diabetes by adding more fat to the diet!

7. Vital energy source

This is my favourite. Fat it is a fantastic fuel that doesn’t burden the body with inflammation, brain fog or energy slumps, unlike its counterpart, glucose. In essence, the body runs a lot smoother when it uses fat for fuel and thus reduces the risk of disease.

Fat abundantly serves our body, so it’s no wonder we crave it. Yet on a regular basis, we deny our body of what it really wants, thinking we are being ‘healthy’.

Contrary to popular belief, fat does not make you fat, or give you heart disease. It does however, enrich our health and we’d do well to include it more in our diet.

If you’re ready to embrace more fat in your diet, have a look at this article—the ins and outs of what fats to eat and how to eat them.

Having educated 🤓 yourself in the origins of the low-fat diet and why we need this vital nutrient to survive, you have given yourself permission to indulge on fats daily, and not just as a ‘forbidden treat’—relish them!

If you’re interested in joining Span, download our mobile app on or contact us at to learn more.

Till next time, 🙌🏽

I’m sure you’re curious about the science behind all this 🔬 Here are some recent medical publications about this topic:

Join Span

We're all different. Unlock what truly works for you.

Request access
Explore Span in...
Span app