If there’s a good versus evil in the nutrition world, it’s salt versus sugar. The two white crystals look similar on the outside but are totally different on the inside—and behave totally different once they’re inside your body.

Salt is composed of two essential minerals, making it an essential micronutrient, whereas sugar is a nonessential macronutrient. And while sugar and salt make up two of the five human tastes (salty, sweet, sour, bitter, and umami), they function in the body in radically different ways.

When you consume refined sugar, your sweet taste receptors signal the brain’s reward system in a way that is much more potent than consuming a piece of fruit—your brain lights up like a pinball machine due to the intense release of dopamine. Unfortunately, those sweet taste receptors don’t signal you to stop eating when you’ve had too much sugar. In fact, the more sugar you eat, the more you crave, creating a vicious cycle of sugar dependence. On the other hand, if you eat loads of the other white crystal (salt), your salt taste receptors "flip" and provide you with an aversion signal. In other words, if you consume too much salt in a meal, your body has a built-in safety mechanism causing you to crave less salt later in the day. Your body is extremely smart when it comes to regulating the intake of essential minerals, especially one as important as salt.

But how much salt should you eat each day? While every guideline and health authority would have you eating no more than one teaspoonful of salt per day, evidence from studies published in the medical literature suggests that most people should eat around 1½ to 2 teaspoons of salt per day. More salt may be needed if you are an avid exerciser and lose salt in sweat or out the urine via coffee intake.

As for sugar, it's best to consume no more than 20 grams (about 5 teaspoonfuls) of added sugars per day for the average adult to avoid negative health consequences.

Over the last few hundred years, the average intake of salt has actually declined. In fact, we now eat one-tenth the amount of salt that we used to consume back in the 1600s in Europe. In those days, we didn't have refrigerators to preserve our food, so everything was packed with salt. During this time of gorging on salt, there wasn’t an obesity or diabetes or hypertension crisis. People back then ate real whole foods and consumed a lot of salt, but they also consumed very little sugar.

During the past few hundred years when our intake of salt was dropping, the intake of sugar was exploding. Indeed, just a few hundred years ago, people consumed just a few pounds of sugar per year. Now that sugar is more available, its average intake has skyrocketed up to 152 pounds of sugar consumed per person per year. That’s a 30-fold increase!

Because people are consuming less salt in general or opting for a healthier and more interesting version, (flakey sea salt or Himalayan pink salt), we are now seeing more iodine deficiency. Iodine is important for thyroid regulation, so we recommend mixing iodized sea salt into your diet.