Is fat really bad for you? Should we devour less salt? And whats wrong with gluten, anyway? A science writer and a consultant cardiologist separate fact from fiction
The great diet food con
Have you ever wondered why people on diets seem to be on and off them forever? Or why its genuinely merely people who struggle with their weight who have extra low-fat mayonnaise in their fridge? Most processed foods branded as diet, low-fat, light or lighter arent what theyre cracked up to be. And if you look at their lengthy ingredients lists, youll realise that theyre not even very good for you.
Take low-fat mayonnaise. When you strip out the fat you have to reinject flavor with sweetness. So an emulsion of eggs and petroleum has become a emulsion of water, maize starch, extra sugar and glucose syrup. Or to put another way: water, sugar, sugar and sugar. Thats an awful plenty of sugar, and because the traffic lights on packets of food dont flash red until a whopping 27 g of sugar is in each 100 g portion thats simply under seven teaspoons a busy shopper wont think twice about selecting this healthy option.
Other culprits are microwaveable low-fat snacks. The high glycaemic index, carbohydrates and sugars aside, producers are so busy bending backwards to limbo under the threshold for each of the other traffic-light categories that they often leave out plenty of healthy foods such as positive fats, fruits, vegetables and fibers. Its why theyre often so tasteless and dont leave you feeling full for long.
The diet food industry is a headless beast driven by marketplace forces: it stimulates good business sense to make low-quality food with effective branding. The only way we can bring it to its knees and stop this totalitarianism of tiny, tasteless snacks is to become savvy both consumers and stop buying them. If you feel yourself being seduced by an alluringly presented diet food and dont have time to interrogate its ingredients, a good rule of thumb is to just say no.
Are calories important ?
We love to ascribe value to things. It helps us make decisions about a jumble of information, like the way we use calories to help us manage what we eat.
The concept entered public consciousness during the first world war when the state used it to make sure people didnt overeat during food dearth. The calorie the unit of energy needed to heat one cm 3 of water by 1C has since became the backbone of our understanding of healthy eating, but at what cost?
In a perfect world it stimulates perfect sense. If you devour more energy than your body needs, then according to the central tenet of Einsteins most famous equation itll be turned into mass a wibbly-wobbly type of mass around your belly and thighs.
The problem is that our bodies dont burn energy with the consistency of a Bunsen burner. We do not assimilate all the nutrients from some foods, says Pete Wilde, a prof at the Institute of Food Research in Norwich. By chewing and eating whole almonds, for instance, we assimilate merely around two-thirds of the energy listed on the label. The calcium in milk and dairy products reacts with fatty acids and again reduces the energy absorbed.
The different rates of digestion of different foods can also affect your appetite and assess the extent to which you end up eating. The more slowly our food is digested the less hungry well feel for longer, Wilde adds. The calories absorbed by two different foods could be the same, but if one food is digested more slowly, itll make us less hungry and less likely to snack.
In how your body its utilization and stores energy, 140 calories of cola is not the same as 140 calories of broccoli. If you want to lose weight by starving yourself, then a calorie-restricted diet is the way to go. Though youll likely bounce back once you start to eat normally. If youre after a sustainable way to be healthy its best to believe a little more about the constituents of your food.
A healthy diet is not about restriction but inclusion of diverse and protective foods. Opting food on the basis of merely calorie content is like selecting their own lives partner on how quickly they can run 100 metres: it might be useful in extreme circumstances, but for your day-to-day life and general wellbeing, its pretty much useless.
Should I lower my salt uptake ?
Whether your salt has been coaxed from a cave by a Tibetan monk or extracted from brine by a human called Gary, its always precisely the same thing sodium chloride. Because its the sodium in salt thats associated with high blood pressure( the only health concern with salt) if anyone tells you fancy salts like sel gris, fleur de sel, Hawaiian ocean salt or pink Himalayan salt are any healthier than the ordinary table stuff theyre wrong.
The matter of whether or not you should lower your salts intake is less cut and dried. Some peoples blood pressure is more sensitive to salt than others. Even scientists are divided about how to construe the evidence on an individual level, but to get bogged down with the scientific disputes would be to miss the point: salt stimulates food taste good.
The first thing that MasterChef magistrate Michel Roux Jr remarks on is a dishs seasoning. Poor Rick Stein must live in constant fear of finally being caught by the salt police he mentions so regularly. Nobody has in the past won a Michelin star with a salt-free menu.
The relationship between salt intake and blood pressure is complicated, says Anthony Heagerty, prof of medicine at the University of Manchester. Lowering salt is advisable on its own population level because many people will respond favourably to an overall lower salt uptake, he says, but teasing out the effect on an individual is harder. An unhealthy diet, excess weight and alcohol play a large its participation in an individuals hazard of hypertension, so if youre worried about blood pressure you can lower your salt, but its perhaps more important to focus on your overall food and alcohol intake.
Fruit and veg rich in potassium, such as mushrooms, spinach and bananas, can help lower blood pressure. Appear out for the mountains of salt used to make low-quality processed foods and snacks more palatable. Employing salt in a sensible way can make the food you cook at home taste better, and, importantly, give you a better manage on what youre putting in your body.
The complicated history of fats
It started in the 1950 s with a suit of mistaken identity. Saturated fats, researchers said, were the main cause of heart disease. The smoking gun? Fatty deposits in patients arteries and studies showing that people in Mediterranean countries where people tend to eat more unsaturated fats like olive oil than saturated fats like butter had a lower hazard of disease.
By the 1970 s the food industry responded. Their answer was trans fatty acids, or trans fats: unsaturated fats transformed by hydrogenation to fit convenient criteria. Once hydrogenated, for example, cotton or vegetable oils would be solid at room temperature to make margarine. Fats could be chemically tweaked to increase the shelf life of cookies and cakes, or to avoid them from breaking down during the repeated reheating done in chip shops and restaurants.
That these trans fats were made from unsaturated ones, the thinking went, entail they were healthier than saturated fats. It was a fallacy supported by the medical community; and one which proved to be deadly.
The increased consumption of trans fats contributed to a peak of heart attacks and strokes during the 1980 s and 90 s. Eating them, it turns out, can also increase your risk of type-2 diabetes, so theres little wonder that producers, at the behest of governments, have been reducing the amount of trans fats in their products.
Theres still no legal requirement for companies to label trans fats as such, cautions Chloe Miles, of the British Dietetics Association. Its important to check the ingredients lists. Appear out for anything with partially hydrogenated oils or fats. The usual suspects are takeaways, tarts, pies, fried foods, cakes, cookies and hard margarines.
Ding dong, pseudoscience nutritionists proclaimed at the jaunt of trans fats, the witch is dead! But they fell into a dangerous trap: they started saying that saturated fats such as butter and coconut petroleum are good for you. This is by no means true. Though angelic compared with trans fats, eating too much saturated fat will damage your health by displacing healthier foods. Trying to replace saturated fats completely with low-fat alternatives, though, means youll be eating more sugar and refined carbohydrates, which will do you worse, so saturated fats should be used wisely to make some healthy foods more satisfying.
The heroes are unsaturated fats from whole food sources. Olive petroleum, seeds, nuts, oily fish and avocados, if prioritised over saturated fats, can help you lose weight and avoid heart disease. And they may even protect against neurological disorders such as depression. The health benefits of these fats is a simple message that should not get lost in a complicated history.