Is Sugar Making You Fat?

Is Sugar Making You Fat?

We are becoming fatter and sicker than ever before. In fact, we have an obesity epidemic. You can’t blame it all on genetics though. Over the past 160 years, our diets have shifted towards eating more processed foods, processed vegetable fats, and eating more sugar in a form of high-fructose corn syrup (HFCS).

What is high fructose corn syrup (HFCS)?

It’s a sweetener made from corn starch; one glucose molecule linked to one fructose molecule. An enzyme in our body called sucrase breaks the chemical bond to release free glucose and fructose molecules.

Fructose in particular is the more lipogenic sugar, about 30% of it ends as fat. It is abundant in processed food and drink in a form of HFCS.

Why is it a problem to consume HFCS? 

There is no transport receptor for fructose on the pancreas and therefore fructose does not stimulate insulin release. If insulin does not go up, leptin (hormone that inhibits hunger) does not go up and the brain does not see that you’ve eaten something. Fructose also fails to suppress “hunger hormone” ghrelin so we eat more. All of these biochemical processes are associated with weight gain!

On the other hand, glucose is used by every cell in the body. When glucose enters bloodstream, it causes insulin to go up and signals to your brain to shut off any further eating.

Historically, we got our dietary fructose from fruit and vegetables. When found in its natural form, fructose comes with plenty of fiber. Think sugarcane.  It’s a stick! How much sucking do you have to do to extract sugar out of it? Today, we are consuming about 15% of calories from fructose alone, which is over the recommended limit of less than 5% of daily intake of ‘free’ sugars.

So why do companies use high fructose corn syrup in foods and drink? Because it’s sweeter and cheaper!

Fat-free foods

Funny enough, we are also fatter today before because we have fat-free foods available.  The problem with fat-free foods is that to make these foods tasty, companies replace fat with fructose. As I discussed above, this alters our hormonal response to sugar and leads to weight gain.

What does the research say?

Fructose effect on fat storage is widely studies animals.  For instance, researches noted that consumption of fructose leads to insulin resistance, impaired glucose tolerance, high insulin levels, high blood pressure, and elevated cholesterol.

In rats, the combination of the high-fat diet with fructose resulted in significant increases in cholesterol. While in humans several short-term studies have implicated fructose consumption as a factor promoting unfavorable lipid profiles.

Many published animal experiments have shown that high-fructose diets induce elevated blood pressure.

Fructose also increases in intra-abdominal fat, which is not seen with glucose consumption. Beverages containing fructose increase post-prandial plasma triglyceride concentrations, which is associated with increased conversion of dietary carbohydrate into fat (de novo lipogenesis).

In summary

1) Continue eating your fruit and vegetables as they are rich in fiber, micronutrients, and antioxidants

2) Consume dietary carbohydrates in the form of glucose (free glucose and starch). This may be particularly important in subjects with existing high cholesterol or insulin resistance

3) Avoid high fructose corn syrup by replacing pop, juice, processed foods with fresh fruit and vegetables

Sugar-Free Dessert Recipe (serves 1)


  • 1 Apple (sliced)
  • 2 tbsps Almond Butter
  • 1/2 tsp Cinnamon (ground)
  • 1 tsp Coconut Oil


  1. Over low heat, warm up coconut oil in a small pan.
  2. Add the sliced apples and saute for about 8 to 10 minutes, until softened.
  3. Add with ground cinnamon and remove from heat.
  4. Transfer to a bowl and drizzle with almond butter.


In Health,

Dr. Anna ND


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