ALL YOU NEED TO KNOW ABOUT FRUCTOSE
- March 23, 2016
Fats have been mistakenly feared for decades, in spite of the integral role they play in our health. The consequential reduction of fat in various food products also led to a significant increase in added sugar, in order to compensate for the loss of taste and texture. Experts believe that this has played a large role in today’s obesity epidemic.
Added sugar, in all its forms, has since been condemned by authorities around the globe, and rightly so.
But it’s also created a lot of confusion around whether fructose, a simple sugar, is good or bad for us. Let’s not make the same mistake we did with fats, and denounce fructose before understanding how it affects us.
Read on to find out how fructose affects our body, the forms that we find in foods, and the ones we should steer clear of.
How Fructose Affects Our Body
Any sugar that we consume is either a simple form or a combination of three sugar molecules: fructose, glucose and galactose. Table sugar, for example, is a form of sugar called sucrose, which is made up of a molecule of fructose and glucose each.
Fructose, which is found in fruits, vegetables and honey, isn’t processed by the body the way the other forms of sugar are.
Glucose can be used by almost every cell for energy. Fructose, on the other hand, needs to be first broken down by the cells in our liver and then converted to glucose. Because of this, our blood sugar levels don’t instantly rise after consuming fructose, as they do with other simple sugars. This makes it possible for even diabetics to tolerate moderate amounts of fructose without losing control of their blood sugar.1
Since the natural sources that fructose is found in (fruits and vegetables) only has it in modest amounts, the chances of anyone consuming too much fructose are very slim.
What about High Fructose Corn Syrup?
Here’s where the problem begins.
Many food products – especially the ones labelled ‘low fat’ – are sweetened with a mixture of glucose and fructose (but is chemically different from sucrose), which is much sweeter than sugar, in order to improve their taste.2
This mixture is called high fructose corn syrup (HFCS).
Because of its ample presence in food products, one would now consume a large amount of fructose in a short span of time – and since fructose is less satiating than glucose, it’s easy to overindulge on fructose when it’s in these forms (unlike in whole fruits) without realising that we’re full.3
When this happens, the liver isn’t able to process the fructose quickly enough; it starts to turn it into fats instead. These fats are then carried in the blood and stored as triglycerides. To top it all off, this procedure even involves the creation of free radicals, which go on to damage our cells, proteins and DNA.
Research has shown that the excessive consumption of HFCS and other sweeteners can also contribute to high blood sugar, in addition to the elevated triglycerides, and the ensuing weight gain. Some studies have also suggested that it could increase our appetite, and creates more ‘belly fat’ – the fat that surrounds our organs in the abdominal area – than glucose alone does.4, 5
Collectively, these conditions can result in obesity, insulin resistance and cholesterol issues, which are underlying causes of lifestyle diseases like type-II diabetes and heart disease.
How Much Fructose is Too Much?
As a rule of thumb, we should generally make sure that the food we eat is worth the calories we are getting from it. This worth is determined by its nutritional value; foods that are high in calories can also be high in nutrition (nuts are a good example of these).
But, when we choose foods that are high in calorie and low in nutrition (like sweet sodas) – that’s something to worry about.
What makes this more complicated is the consumption of foods that sound (and are often sold) as though they were healthy, but aren’t always.
Fruit juices are a great example of this.
To understand why, let’s take a look at a glass of orange juice. A whole orange, of about 130 grams (not the juice), has approximately 62 calories, with 12 grams of sugar and 3 grams of dietary fibre. A freshly squeezed glass of orange juice (250 grams), on the other hand, has 112 calories, with 21 grams sugar and 0 grams of dietary fibre.
The amount of fructose in the juice is higher than in the whole orange, because it took more than 1 orange to make, and has very little dietary fibre to stall the breakdown of the sugars. Along with its other benefits, dietary fibre is also known to reduce triglycerides and LDL in the blood.6
The freshly squeezed orange juice also lacks nutrients called ‘flavonoids’, since they’re lost when the pulpy white part of the orange is removed. These flavonoids otherwise work together with the vitamin C content of oranges, supporting our health through their interaction.7, 8
With more calories and more sugar than the whole fruit, fruit juices also have far less nutrients and fibre.
The packaged varieties (especially the ones with HFCS) are, predictably, far worse because they contain even more sugar – and, therefore, more calories – with a smaller amount of vitamins and minerals.9
So, What Must We Do?
1] Limit our intake of table sugar and food products with added sugars
According to the World Health Organisation (WHO), only 5% of our daily calorie intake should consist of added or ‘free’ sugars, which equates to about 5-6 teaspoons (25g) for women and 7-8 teaspoons (35g) for men.
A single can of a fizzy drink contains nearly 9 teaspoons. It’s easy to see how people can easily reach and even cross the recommended daily amount, and why sugar is said to be excess in the modern diet.
2] “Un-sweeten” our diet
We can cut down on non-nutritive forms of sweets, like desserts, and include nutrient-rich ones, like fruits. For those who are addicted to sugar, reducing the amount of added sugars as well as artificial sweeteners in the diet is believed to eventually decrease sugar cravings.
That said, completely avoiding carbs isn’t recommended either; fruits, vegetables and whole grains give us vitamins, minerals and other compounds that are very beneficial for our health.
3] Increase the dietary fibre in our meals
As we saw in the orange juice example, dietary fibre can go a long way in averting sugar’s damaging effects.
Even statistically speaking, Indians eat about half the amount of fibre that we ideally should. The recommended dietary fibre intake is between 25 and 40 grams a day for adults, and most of us don’t even come close to hitting that target.10
With about 1 to 3 grams of fibre per cup, fibre-containing foods should feature frequently and abundantly in our meals. These include whole grains, legumes, dried fruits, seeds and some fruits and vegetables (bananas, apples, carrots, broccoli, Brussells sprouts and spinach). Having fibre supplements and fibre-fortified foods is also a great way to reach the recommended fibre intake.
Following these three steps won’t require a monumental change in one’s daily habits – just simple adjustments to make way for better practices and, ultimately, a healthier lifestyle.
1. McGrane MM. Carbohydrate metabolism: Synthesis and oxidation. Saunders Elsevier: Missouri, 2006.
2. Hanover LM, White JS. The American journal of clinical nutrition 1993, 58(5): 724S-732S.
3. Page KA, et al. Jama 2013, 309(1): 63-70.
4. Stanhope KL, et al. The Journal of Clinical Investigation, 119(5): 1322-1334.
5. Lowette K, et al. Front Nutr 2015, 2: 5.
6. Anderson JW. Dietary fiber prevents carbohydrate-induced hypertriglyceridemia, vol. 2.
7. Kaack K, Austed T. Plant Foods Hum Nutr 1998, 52(3): 187-198.
8. Peel T. Vitamin C: New Research. Nova Science Publishers, 2006.
9. SelfNutritionData. Nutrition Facts: Minute Maid® Orange Juice. California, USA: Condé Nast; 2014.
10. Slavin J. Nutrients 2013, 5(4): 1417-1435.