Never before in the history of human kind have we had a need to lower our blood sugar. This is because simple sugars such as fruit and honey were extremely rare and hard to come by in nature. Other starchy carbohydrates such as grains and root vegetables which provided a staple in the diet of many indigenous cultures provided less than 40% of dietary calories according to the empirical based research of Weston A. Price. These foods cost a high price in labor to gather, burning precious calories, and contained very little fuel (in the form of calories) compared with fats and proteins. In other words carbohydrates are turned into fuel and that fuel is used very quickly leaving you hungry more frequently. In modern times we've compounded this issue of using this fast cheap form of food out of proportion to other nutrients by refining our carbohydrates.
Refining would involve turning these grains into flour by grinding them (even whole grains) which would speed up the absorption of sugars into the blood. Or a further refinement would be for example polishing a rice grain to remove the outer shell yielding white rice or white flour turning these complex carbohydrates into a highly refined form of sugar. It doesn't need to taste sweet to be sugar! Likewise if you refine fruit (into juice), agave plants, sugar cane, sugar beets, you take away the natural fibers and nutrients found in these whole foods and you are left with a refined pharmaceutical grade chemical extraction. In the case of honey the bees synthesize this extraction for us and in its raw form contains some vitamins and nutrients which provide a mild buffer to sugar absorption. The problem with the body receiving these high doses of sugar (several times a day for most people) is that it creates a crisis inside the body involving the liver, pancreas, and adrenal glands.
Blood sugar levels need to be maintained within a very small margin in order for us to stay alive. So your body has certain defenses against a rapid rise in blood sugar levels such as: 1. Storing a small amount in the liver, 2. Release of insulin from the pancreas which pushes the sugar into cells, 3. Stimulating the release of adrenal hormones to counter elevated blood sugar levels. Although it is extremely common to eat these refined sugars in large quantities in recent modern times it is definitely not "normal" in human history. Blood sugar surges or spikes can contribute to arterial sclerosis- by damaging arterial walls, diabetes- by causing insulin resistance, obesity- when the body puts a fat cell around the sugar molecule for storage, and cancers- caused by organ tissue damage from the storage of excess sugars.
Food for thought- You can keep your blood sugar levels in check by maintaining no more than %20 percent calories from starchy carbohydrates, %20 from non starchy carbohydrates, %30 from proteins (animal source), %30 natural- un adulterated fats. Most indigenous cultures got a higher # of their total daily calories from fats from %30 up to %80 and were immune to our modern diseases.