Some of our most widespread health and fitness facts are based on little more than marketing.
The idea of 10,000 steps a day has become one of the popular health mantras of the past decade, with the rise of Fitbits and other wearables all fueling an obsession with counting steps.
That number of steps actually completely random, taken from a Japanese boardroom in the 1960s. Few people realize it, but the Yamasa company came up with the number as a way to promote the world’s first pedometer ahead of the 1964 Tokyo Olympics.
Instead, actual research has suggested that between 6,000 and 8,000 steps a day could be good for preventing chronic disease.
8 hours of sleep
At the time of the Industrial Revolution, a daily regimen of eight hours of work, eight hours of relaxation, and eight hours of rest was commonly prescribed. That seemed like a nice distribution to the factory directors.
But we now know that the amount of sleep we need is highly individual and determined by a complex mix of genetics, age, medical conditions and lifestyle. Some people can function perfectly in less than six hours, while others need more than ten hours to feel their best.
Two liters of water a day
Two liters of water a day, or about eight glasses, has been standard advice for decades, but our fluid needs vary widely depending on how much we exercise, the weather, the climate and our age.
Depending on the circumstances, people may need as much as six liters if they exercise a lot in hot weather, or as little as one litre.
Breakfast is the most important meal of the day
Our modern obsession with breakfast dates back to the 1920s, when early marketing campaigns by cereal manufacturers placed great emphasis on the supposed healthiness of breakfast. As people became more and more concerned with the concept of vitamins, savvy cereal brands began touting the nutritional value of their products, even claiming in recent decades that breakfast could help you lose weight.
But whether breakfast is necessary at all remains a matter of scientific debate, with nutritionists saying its health benefits depend on what you actually eat. A breakfast consisting of highly processed foods and high sugar content is likely to do more harm than good.
2,000 calories per day
Our recommended calorie intake depends, among other things, on the level of physical activity
The myth is that 2,000 calories a day for women and 2,500 for men would be ideal.
But just like sleep and water intake, our calorie needs depend on many things, including age, gender, height, weight, and activity levels. Some people will need to reduce or increase their calorie intake to maintain a moderate weight.
Many nutritionists question the relevance of the calorie fix in our diets because not all calories are created equal.
“Calories don’t account for the energy our cells need to metabolize food to use it,” Giles Yeo, a professor of molecular neuroendocrinology, told the Daily Telegraph. “A calorie of protein makes you feel fuller than a calorie of fat, because protein is more complex to metabolize. You could aim to eat 2,000 calories a day, but how much energy your body actually absorbs depends on whether you eat sugar, celery or steak.