Websites, advertisements and well-meaning popular articles routinely warn us about nasty “chemicals” lurking in our homes and kitchens. Many tout the benefits of switching to a “chemical-free lifestyle". The problem is: the word “chemical” is entirely misused in these contexts. Everything is a chemical – common table salt (sodium chloride), for instance, and even water!
The chemicals in our diet are often put into four broad categories: carbohydrates, proteins, fats and lipids, and everything else. This final group has no defining characteristics but includes vitamins, minerals, pharmaceuticals and the hundreds of trace chemicals each of us consumes every day.
Of course, there are toxic and harmful chemicals, but just as many are completely fine for human consumption. So here’s a handy guide to the chemicals in your kitchen and what they mean for your health.
The macronutrient chemicals
Proteins, lipids (such as fats) and carbohydrates are known as the macronutrients. These provide most of our daily energy needs.
Despite 118 known elements in the periodic table, these three categories predominantly contain just four elements – carbon, hydrogen, oxygen and nitrogen – with trace amounts of the remaining elements.
Chemicals called amino acids link together to create proteins. The richest sources include meat and eggs, but significant amounts are also found in beans, legumes and wheat flour.
Carbohydrates contain just carbon, hydrogen and oxygen atoms, all connected in very particular ways. “Carbs” include sugars, starch and cellulose, all of which are digested differently.
While sugars are one type of carbohydrate, artificial sweeteners, such as aspartame and saccharin, are not actually carbohydrates.
Despite concerns about the [health effects of artificial sweeteners, the health spotlight has recently been on the natural sweeteners: the sugars. White sugar (sucrose) and high-fructose corn syrup (a mixture of fructose and glucose) have been linked to a range of widespread health conditions.
Just like carbs, fats only contain carbon, hydrogen and oxygen, but gram for gram release more than twice the dietary energy of either protein or the carbs. Perhaps it’s for this reason fats have copped a lot of bad press for longer than the sugars. Nevertheless, some fat is essential for a healthy diet.
Acids and bases
Acid sounds bad. But there are many acids sitting benignly in our pantries and fridges.
Consider varieties of food and drink that are acidic. A classic example we often hear is that Coca-Cola has a pH value of about 3.2 (lower means more acidic, with 7 being neutral). That’s strong enough to remove rust from metal. And it’s true, thanks to the phosphoric acid in Coke.
As it happens, the human stomach also contains phosphoric acid (as well as hydrochloric acid), and this has an even stronger acidic pH value. Actually, apples and oranges have a similar pH value to Coke, and lemon juice is ten times more acidic.
The acidic characteristics of food and drink combine with other chemicals to provide flavour. Without some acidic character, many foods would be bland.
Chemically speaking, the opposite of acidic is known as basic, or alkali. While acidic substances have a pH of less than 7, basic foods have a pH greater than 7. Examples of basic foods from the kitchen are fewer, but include eggs, some baked products like cakes and biscuits, and bicarb soda.
So next time you hear someone say “I don’t like to put chemicals into my body”, feel free to chuckle. EVERYTHING is made of chemicals. We’d be in a bit of strife without chemicals, not least in the kitchen.