Honey and agave are natural sweeteners considered healthier than sugar. However, both agave and honey contain sugar themselves and should only be consumed in small amounts. Honey is slightly richer in calories and carbs, and has a much higher Glycemic index. On the other hand, agave has much higher fructose content, which is bad for health.
edit Sugar Content
Both agave and honey contain glucose and fructose. However, agave contains a higher percentage of fructose, which is considered less healthy than glucose, as fructose is more likely to be stored as fat.
edit Calorie content
One teaspoon of agave contains 5g of carbohydrates. Agave contains small amounts of calcium, potassium and magnesium, but not enough to be nutritionally significant.
edit Other Health Benefits
A scientific study to measure the effectiveness of honey for children with acute cough found that honey was effective in reducing frequency of cough, reducing bothersome cough and improving the sleep quality of the child but had no significant benefit in resolving severity of cough. The effects of honey were no different than Dextromethorphan, which is available under brand names like Robitussin Pediatric Cough Suppressant, Tylenol Simply Cough and Vicks 44 Cough Relief.
edit Glycemic index
A product’s glycemic index (GI) shows how quickly its energy (from carbohydrates) is released in the body. If it is released too quickly, it can disturb blood sugar levels. Low GIs show a slow release of energy, and are under 55.
Agave has a GI of between 10 and 19, while pure honey has a GI of 58.