So, what sugars are safe? How are they different? Sweeteners like honey, cane sugar, and agave have varying ratios of glucose to fructose. This determines how they affect your blood sugar levels, liver function, and immune response.
Here’s a breakdown of the glucose/fructose content of the most common sweeteners, and how they rank on the good/better/best scale.
To determine the best and worst sugars, we’ll weigh the ratios of glucose to fructose and the glycemic index and glycemic load of each. Glycemic load values below are based on a serving size of one tablespoon.
Glycemic Index (GI): How fast a food’s sugar content is absorbed into the bloodstream
Glycemic Load (GL): How a food’s sugar will impact your insulin response – taking into account the carbohydrates, fiber, and serving size
While GI measures how fast sugar is absorbed, it doesn’t take into account the amount of sugar that food contains relative to it’s fiber and portion size. Thus, as health columnist Dr. Laina Shulman explains, “Although the sugar in the carrots is absorbed into the bloodstream quickly [GI of 74], there is not a lot of sugar to begin with [GL of 2]. As you can imagine, the same amount of dense white pasta would have both a high glycemic index  and a high glycemic load .”
Low GI = 55 or less
Medium GI = 56 – 69
High GI = 70 or more
Low GL = under 10
Medium GL = 10 – 2
High GL = 20 or more
High Fructose Corn Syrup (HFCS)
Derived from corn starch, HFCS undergoes processing that converts half of the naturally-occuring glucose into fructose.
Chemically, HFCS appears very similar to sucrose: both are made up of 50 percent glucose / 50 percent fructose. But they behave very differently once metabolized.
HFCS fructose molecules are “free and unbound” – ready to be converted into fat immediately. In contrast, Princeton researchers report, “every fructose molecule in sucrose [table sugar] is bound to a corresponding glucose molecule and must go through an extra metabolic step before it can be utilized.” Thus, HFCS fructose is immediately available for fat conversion, whereas sucrose needs further breakdown.
The two most common HFCS mixtures are HFCS-55 (containing 55% fructose) – typically added to sodas, and HFCS-42 (42% fructose) – typically added to processed foods.
High fructose corn syrup wasn’t discovered until 1971. In 1982, when the cost of sugar imports jumped, it became cheaper to sweeten food/drink with domestic HFCS. Thus, HFCS’s popularity skyrocketed – just look at that line graph climb:
courtesy of Precision Nutrition
Contains 90 percent fructose (that’s more than HFCS!) – making it one of the highest fructose levels among sweeteners.
Be wary of the “raw” claim. This syrup is made from agave juice which is filtered, hydrolyzed, then boiled to concentrate the sugars – this is hardly a “raw” product.
Because of it’s high fructose content, the sugars are metabolized in the liver, and don’t enter the blood stream – resulting in a deceptively low rank on the GI & GL scale, but don’t be fooled (we learned about the dangers of fructose above).
No nutritional value, all vitamins and minerals are stripped out during the refining process. This is a bad sugar, indeed.
True, agave has a low glycemic index, but what it does is far worse than raise insulin levels: it can raise your triglyceride levels, trigger inflammation, and otherwise damage your liver. So don’t fall for the agave hype.
Raw honey has a glycemic index of about 30, relatively low among sweeteners, but be wary of processed honey which has a much higher GI (around 75).
Another reason to choose raw: In order to increase the sweetness, processing destroys much of honey’s natural benefits.
Contains natural antioxidants, minerals, vitamins, amino acids, and enzymes. Studies claim it can boost immunity and even reduce allergies.
My Favorite Sweet Snack
I love morning oatmeal with honey, raisins (make sure they’re the unsweetened kind), and pistachios. Or try a snack of sprouted grain toast with almond butter, honey, and cacao nibs. Another favorite is sweet potatoes roasted with coconut, raw cane sugar, and coconut oil.
Maple syrup is the concentrated sap of the maple tree, collected from a tap bored into the truck, then boiled to evaporate the excess water.
Although low in free fructose, it is made up of about 66 percent sucrose (which is half fructose).
A significant source of manganese, iron, and calcium.
Choose darker grades, which have higher levels of vitamins and minerals.
Molasses is actually a byproduct of sugar processing
Equal parts fructose/glucose
Natural source of iron, calcium, magnesium, potassium, phosphorus, copper and zinc (which are usually extracted in table sugar production)
Great for baking
Coconut Palm Sugar
GI: 35 GL: 1.4
Made from the nectar of the coconut palm
Low in free fructose, but is comprised of 70 to 79 percent sucrose (which means it’s still 35 – 45 percent fructose)
Not to be confused with palm sugar, which derived from a different type of palm tree
Contains iron, zinc, calcium and potassium, along with some short chain fatty acids, polyphenols, antioxidants – and even a little inulin fiber to slow the insulin spike
Fairly new on the market, its nutritional profile is still contested, read a further analysis from Authority Nutrition here.
Because nature is awesome, and she’s been doing this whole glucose/fructose thing for centuries, eating fruit sugar is safe. However, some fruits have better ratios of sugar to fiber, which prevents an insulin spike, and delivers more sustained energy.
Blueberries, strawberries, and grapefruit: Super high in antioxidants and fiber, these fruits are powerhouses of taste and nutrition with relatively low sugar.
Still Awesome, But Don’t Go Craycray:
Mangos, papayas and nectarines: Super high in sugar and low in fiber, these fruits are still delicious and natural, but are more likely to give you a blood sugar spike. Still, they’re way preferable to a snickerdoodle.
How Fruits Rank:
Shoot for high-fiber, low-sugar fruits for the most health benefits and steady energy (e.g. the lower right-hand quadrant of this graph):
Mark Sisson of Mark’s Daily Apple outlines his picks for best and worst fruits according to his Primal Diet.
So, What Sugars Can I Eat?
Let’s be real here. I’m not saying don’t eat sugar ever, ever. Because we all know our willpower has limits. But if you choose fruit over refined sugar, and pay close attention to added HFCS, you won’t be at risk of sugar-induced heart disease and chronic stress.
Sure, it might not satisfy your HFCS-loving sweet tooth at first, but you canbeat sugar cravings. And you will feel so liberated.
Eat naturally-occuring sweeteners occassionally.
Look for low-fructose, raw, and unrefined sweeteners. A lil’ maple syrup and honey won’t hurt you, but shoot for no more than a teaspoon per serving.
Stay away from HFCS.
Get off the corn crack, guys. Eating high fructose corn syrup will make you fatter and more addicted. Watch for it on ingredient lists and nutrition labels.
TIP: If you gotta get your sugar fix (’cause sometimes an apricot just won’t cut it), splurge on a raw cane sugar cookie or small raw cacao chocolate bar. Sucrose is much easier to metabolize than HFCS. It will still give you a sugar high/crash. But small indulgences will keep you from binging later on. Our rule: Be kind to yo’self. But avoid the sugar health risks.
I’d suggest paying closest attention to the total sugar content first, then to any nutritional benefits, and finally to the fructose content. Blueberries might have a relatively equal fructose/glucose ratio, but they offer huge antioxidant benefit. On the other hand, dried apricots have a lower fructose ratio, but their overall sugar content dwarfs many fruits ounce for ounce. Raw honey and coconut sugar likewise offer solid nutritional benefit for their sugar content compared to other sweeteners.
If you’re going to eat sugar, get it from fruit or naturally occurring sweeteners. With that being said, to minimize the effect on your blood sugar, minimize sugar consumption across the board if your primary goal is weight loss.