Who says breakfast is the most important meal of the day? And why does spinach make you strong? It sounds like conventional wisdom, but most of it was cooked up by ad men
By:- Arwa mahdawi & Amy Flaming
came first, the chicken-is-healthy study or the eggs-are-unhealthy study? Nutritional advice is notoriously nebulous, and food groups regularly alternate between demonisation and deification. Fat makes you fat; fat makes you thin; carbs are basically crack; carbs are back. Corporate agendas are behind much of this confusion. But, more worryingly, they’re also behind many of the food “facts” we take for granted. Much conventional health wisdom is actually commercialised wisdom: the result of canny marketing campaigns or industry-funded studies. Even if you think you’re above advertising, immune to the seductions of pseudoscience, you would be surprised how many marketing myths you may have inadvertently swallowed.
Breakfast of chumps
Let’s start with breakfast. There’s no conclusive evidence a morning meal makes you lose weight and feel great, but the idea that breakfast is the most important meal of the day is widely ingrained. This is largely thanks to the efforts of grain companies. Kellogg’s, for example, funded an influential study that linked breakfasting on cereal with lower BMI. And The Quaker Oats Center of Excellence financed research showing that a daily breakfast of porridge reduces cholesterol.
Big Cereal isn’t alone in bigging up breakfast with biased science; bacon is also to blame. In the 1920s, PR man Edward Bernays was tasked with increasing bacon consumption in the US. At the time, most Americans ate a light breakfast; Bernays figured a good way to increase bacon consumption would be to increase breakfast consumption. So, he asked doctors to confirm that “a hearty breakfast was better than a light breakfast to replace the energy lost by the body at night”; 4,500 doctors agreed and Bernays got the media to report the results, strategically placing bacon adverts by the headlines. Today, 70% of bacon eaten in the US is eaten at breakfast.
Drink eight glasses of water a day
No one knows where this dictum originated. A 1945 US Food and Nutrition Board document once said that we need 2.5 litres a day, but it also said that much of this can be obtained from food. In any case, how much we need fluctuates, on any given day, according to how active we’re being, what we’re eating, whether we’re ill, and the weather. This is why our bodies handily tell us when we need more water (although old age can stymie thirst signals). Don’t listen to anyone who tells you you’re already dehydrated when you feel thirsty. Someone made that up.
In 2011, Margaret McCartney, a GP, wrote to the BMJ to highlight the lack of evidence for hydration advice, including the NHS’s more modest recommendation of six to eight glasses (or 1.2-1.9 litres) a day. She name checked an initiative called Hydration 4 Health, which promotes the benefits of drinking extra water to the public and to doctors. Hydration 4 Health recommends two litres for men and a little less for women (1.6 litres). It is sponsored by the French company Danone, which owns Evian, Badoit and Volvic mineral waters.
A review study published in the Journal of the American Society of Nephrology in 2008 found “no clear evidence of benefit from drinking increased amounts of water”. The potential perks the study investigated included improved kidney function and detoxification, clearer skin, fewer headaches and reduced calorie consumption due to feeling fuller. However, the authors wrote, “although we wish we could demolish all of the urban myths found on the internet regarding the benefits of supplemental water ingestion, we concede there is also no clear evidence of lack of benefit”.
You lose the most body heat from your head
It’s easy not to question this. Heat rises, after all. Roofs need insulation and so do heads. Except, now you mention it, so does any part of the body when it is cold. It is thought the confusion arose from the misinterpretation of an experiment carried out by the US military in the 1950s. It was freezing and only the participants’ heads were exposed to the elements, so, of course, that is where they shed the most heat. More recent investigations have found that the head loses as much body heat as any other exposed body part. Bad news for the hat industry.
Reading in the dark ruins your eyesight
Poppycock. Reading in dim light can be challenging, to the point of being deeply irritating. It can even give you a headache and result in tired or strained eyes. However, says the College of Optometrists, “reading in dim light or in the dark is highly unlikely to cause any permanent damage to your eyes”. Some studies have found that myopia is more common in highly educated cultures, in which children grow up doing more close work, such as reading, but the connection could simply be that richer populations have better access to diagnosis from eye specialists. Ideally, however, when reading after dark, light should shine directly on to the page, and not come from over your shoulder, thus causing glare.
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