Outing the baddies: unhealthy fats and where to find them

It's not just his puppy-dog eyes, curly hair and striking musculature that have taken Joe Wicks to the top of the charts for paperback non-fiction. The personal trainer is cashing in on a secret that all fitness instructors know: being fit and healthy is as much about diet as it is about exercise, maybe even more so. Some give the ratio at 20 per cent exercise and 80 per cent diet.

London cardiologist Dr Aseem Malhotra blames the food industry for encouraging the idea that sufficient exercise can counteract the effects of unhealthy eating. "That is unscientific and wrong. You cannot outrun a bad diet," he writes in a piece in the British Journal of Sports Medicine.

Regular exercise is key to staving off serious disease, such as diabetes, heart disease and dementia, Malhotra and co-authors Timothy Noakes and Stephen Phinney write, but our calorie-laden diets now generate more ill health than physical inactivity, alcohol and smoking combined.

Joe Wicks: The popular personal trainer knows that nutrition is as important as exercise. Photograph: Getty Images

So if you want to improve your fitness levels, make it easy on yourself and get your diet right first. You don't even have to buy one of Wicks's three Lean in 15 books on the bestseller list.

The simplest way to get started is to see food for what it can be: nutritious, tasty and energising. Forget about simply counting calories. Rather than worrying about nutrition labels telling you how much fat, sugar and carbohydrates there are, consider the nutritional value. Are you eating recognisable food? Or are you heating up packets?

In The Omnivore's Dilemma, respected American author on food and nutrition Michael Pollan writes: "Eat food. Not too much. Mostly plants." He later explained that if your grandmother would not recognise what you plan to eat as food, you probably should not eat it. In his later book of Food Rules, he writes: "If it came from a plant, eat it; if it was made in a plant, don't."

Processed food

So what’s wrong with processed food? Part of the problem is the unhealthy fats and oils they use. Just because something has been passed for consumption doesn’t mean it’s a good idea to eat it.

Even as we hail healthy fats as the good guys, we have to acknowledge that there are baddies out there lurking on the supermarket shelves that are best avoided. These include trans fats, which are also known as hydrogenated or partially hydrogenated vegetable oils, and processed vegetable oils.

Take trans fats. These are fats that have been treated to make them easier to work with, but therein have lost their nutrition.

They are cheap, malleable, and help products seem fresher for longer and to taste better. But they are bad for your health and avoiding them is one of the simplest steps you can take.

A number of countries, such as Iceland, and companies have already limited their use and the EU is considering legislation on the issue. MEPs recently passed a resolution that the EU should place mandatory limits on trans fats. According to the European Commission, only one in three consumers in the EU knows about trans fats, which it says shows that labelling measures are inadequate. So a ban may be on the way.

Health benefits

In their resolution, the MEPs highlighted the "rapid and significant health benefits" that Denmark has seen since it introduced a limit of 2 per cent of trans fats in oils and fats in 2003, including a significant reduction in deaths caused by cardiovascular disease.

But what’s really worrying is that these fats have been in processed foods since the 1950s and the truth about the harm they can do has been out since the 1990s. Yet action is only now being taken. That’s why you are better off sticking to real food.

Unless Donald Trump awakens to what is going on, lumbers to his beautiful desk and tears up another piece of legislation, trans fats are on their way out in the US too.

The US Food and Drug Administration has ruled that they are not "generally recognised as safe" (GRAS), which is a classification. So they are banned from American foodstuffs from 2018. It also said the action is expected to reduce coronary heart disease and prevent thousands of fatal heart attacks there each year.

Heart disease is still the leading cause of death in Ireland, according to the Central Statistics Office. In a recent report the British Medical Journal says trans fats have also been associated with Alzheimer's, infertility, obesity and some cancers.

Nobody goes into the supermarket looking for a packet of hydrogenated vegetable oil, but if you opt for cheaper biscuits, cakes or margarine, particularly those from the US, that may be a large constituent.

Vegetable oil

Another ugly ingredient to watch out for is vegetable oil. The processing of many vegetable oils is so heavy-handed it removes all nutritional value.

Take cooking oils, such as sunflower oil or corn oil. To make them attractive to consumers food companies sell oils that do not discolour or go rancid in bottles on the supermarket shelves. They have none of the characteristic flavour of the original plant such as corn.

This is achieved using a refining process that includes heating, extraction using solvents, bleaching and deodorising. The finished product is “pure calories” as all nutrients have been removed or destroyed.

The processing results in the loss of chlorophyll, calcium, magnesium, iron and copper. During refining it loses free fatty acids, phosolipids and minerals. Bleaching removes chlorophyll, betacarotene and flavour. Deodorising removes free fatty acids, vitamin E and more flavour compounds. If it is then hydrogenated, essential fatty acids are lost.

It’s best not to cook with those oils anyway, according to Prof Martin Grootveld, professor of bio-analytical chemistry and chemical pathology at DeMontfort University, Leicester. When fats and oils, such as corn oil and sunflower oil, are heated, the molecular structure changes, producing chemicals called aldehydes that may cause heart disease and cancer. He advises using butter, olive oil or coconut oil instead.

Avoid the baddies

So what can you do to avoid the baddies? Choose cold-pressed oils such as olive oil or rapeseed oil even for cooking. Avoid highly processed oils such as sunflower and corn. Or use them sparingly.

Avoid processed foods. Eat high-quality treats. If you want to have cake or biscuits, buy them from a small baker or a shop that makes its own. Better yet, make your own treats and use butter, olive oil or coconut oil.

If you are buying anything in a packet, check the back for the words “trans fat”, “hydrogenated vegetable oil” or “partially hydrogenated vegetable oil”, or any version of that.

Get your diet right first and you will have the energy and enthusiasm to work out. You will wake up keen to fit exercise into your day. But that’s a topic for another day.