We'll start with what the two have in common.
Both added sugars and free sugars are dietary sugars that provide rapidly-absorbed, concentrated doses of fructose. When consumed, their large doses of fructose overwhelm the liver's ability to metabolize fructose. The liver responds by doing the most efficient thing it can do with fructose--it converts fructose to fat, which, over time, leads to metabolic syndrome by contributing to:
- fatty liver disease (a precursor to diabetes)
- liver insulin resistance (a precursor to diabetes)
- increased small, dense LDL cholesterol
- increased triglycerides
- increased uric acid (which contributes to hypertension)
Added sugars are sugars added to food during processing. Manufacturers add sugar to their products because it tastes good, consumers like it, and sugar is a preservative that extends the shelf life of processed foods.
You'll find added sugars in the ingredient list of a processed food. There are now more than 56 names for added sugars used by the food industry, and you will commonly find multiple added sugars in a single product.
The term "free sugars" is inclusive of added sugars, but also includes sugars found naturally in foods like fruit juice and honey.
The naturally-occurring sugars are "freed" when fiber is removed during processing (such as juicing) or simply because fiber was never present in the first place (honey). Fiber slows down the absorption of sugar. When it is not present, free sugars are concentrated and act just like added sugars on the liver leading to the development of metabolic syndrome.
Under this definition lactose (milk sugar) when naturally present in milk and milk products and sugars contained within the cellular structure of foods (particularly whole fruits and vegetables) are excluded.
The 2015 Dietary Guidelines recommend limiting your calories from added sugar to 10 percent of total calories or less.
Since free sugars are metabolically equivalent to added sugars, the 10 percent guideline applies to both--combined.
So calories from added sugars plus calories from free sugars should be less than 10 percent of your total daily calories, according to the Guidelines.
The American Heart Association and the World Health Organization make the same recommendation, but the World Health Organization takes their recommendation a step further and advises that limiting calories from free sugars to less than 5 percent provides additional health benefits.
We at the IRN suggested limiting your calories from free sugar to as close to 0 grams per day as you can. The metabolic consequences of sugar are dose-dependent, meaning the more you consume, the worse off you are.
Make most of your days sugar-free for maximum benefit. We understand that may be difficult to do overnight, but think of it as a progression. Start with one source of free sugar in your diet, and find a sugar-free alternative. Once you're comfortable with that change, address another source of sugar in your diet.
The simplest way to cut back on free sugar, is to eliminate processed foods and beverages. Focus on eating whole, real foods that don't have sugar added to them and don't have their protective fiber removed either.
When faced with a challenge, know that your efforts to reduce your sugar intake will convey health benefits. A recent study conducted by Dr. Robert Lustig and colleagues and published in the journal Obesity found that reducing free sugars in the diets of obese, metabolically ill children for just 10 days significantly improved all of their metabolic markers--blood glucose, insulin, liver fat, uric acid, blood pressure, triglycerides, cholesterol, and even their body weight.