The Secret Behind Protein Bars
Protein bars are becoming more popular by the day, and one of the companies leading the charge is Quest. Originating in the US, Quest were one of the first protein bar companies to target the general gym goer looking to improve their health. 20g of protein is the go to number as people rush from the gym
Taking a glance at the pack, they do appear remarkable. A 170 calorie bar includes
- 20 g protein
- 4 g net carbohydrates
- 1 g sugar
- 15 g fiber
You’d think that with these nutritionals there is no way Quest bars can taste in anyway good. Astonishingly they are far sweeter than expected. How can this be? Let’s delve into the ingredients to find out.
The secret lies in a sweet syrup called Isomaltooligosaccharide (IMO). It is nutritionally labeled as 100% fiber by Quest. IMO is naturally found in small quantities in fermented products but Quest use a synthetic version made from starch.
How is IMO sweet?
Some of the IMO syrup is broken into the simple sugars glucose and fructose which have a high sweetness. It is also worth noting that quantities of glucose and maltose are found in IMO syrup contributing to the sweetness (2).
Is IMO really 100% fiber?
IMO has a glycemic index of 35 and therefore it should not be considered as 100% fiber (1). In fact the main molecule isomaltose is actually digested and absorbed as a sugar (2). The protein bar Kill Cliff use a high quantity of IMO in their bars but do not include it as a fiber in their nutrition facts labelling. This suggests that Quest may be over stating their fiber content quite drastically.
Is there such thing as too much fiber?
The recommended fiber intake for adults is about 25 g per day. One bar contains a whopping 68% of your recommended fiber intake for the day. Eating such a large quantity in one go can cause gas and abdominal cramps as well as inhibit the absorption of key nutrients including iron, magnesium and zinc. High intakes of fiber from natural whole foods results in high consumptions of these minerals, meaning the inhibition of absorption is insignificant.
Fiber can come in many forms and eating a varied diet provides a diverse range of fibers, feeding different strains of microbiota in your gut. The problem with loading a bar with IMO is that it only feeds one specific subset of a person’s microbiota.
What else is making Quest bars sweet?
Sucralose (E number E955) is another major contributor to the Quest bar sweetness. The 0 calorie sweetener does so without adding any calories whatsoever to the bar. It is used in small quantities due to its astounding sweetness, 600 times greater than sucrose (3). Some small scale studies have suggested sucralose poses a risk of diabetes, cancer and obesity but larger clinical studies have shown it safe (4).
Why ditch IMO in the US?
We discovered Quest have completely replaced all IMO with corn fiber in America. Quest say this change is because corn fiber is far better than IMO. Their website states advantages of corn fiber “include anti-inflammatory effects, improved immune response, and an improved and more predictable blood sugar/insulin response, just to name a few.” (5). In Europe, Quest still use IMO in most of their bars. This begs the question, are us Europeans not good enough for the “whole host of health benefits” of corn fiber?
We suspect that Quest ditched IMO because
- of a lawsuit taken against them for misstating fiber and carb content.
- over time Quest bars become rock solid due to the IMO.
- the bars raise blood sugar far greater than a 4 g net carb bar should
So, should I eat these bars?
We wouldn’t think of them as overly healthy but they are probably a bit better than a lot of snack options out there. These bars don’t come cheap though. With a price tag of approximately €3.40/£2.50, we won’t be buying them anytime soon. If you’re looking for that 20 g protein hit, we would recommend 150 g strained Greek style yogurt paired with 30 g of your favourite ProMix. Many nutritionists are moving towards real food options like this to boost protein post training for atheletes.
- G Sheng CD-l, Li-li Wan. Determination of glycemic index of xylitol and isooligosccharide. Chinese Journal of Clinical Nutrition. 2006;14(4):235-7.
- Goffin D, Delzenne N, Blecker C, Hanon E, Deroanne C, Paquot M. Will isomalto-oligosaccharides, a well-established functional food in Asia, break through the European and American market? The status of knowledge on these prebiotics. Critical reviews in food science and nutrition. 2011;51(5):394-409.
- Binns NM. Sucralose – all sweetness and light. Nutrition Bulletin. 2003;28(1):53-8.
- Grotz VL, Munro IC. An overview of the safety of sucralose. Regulatory toxicology and pharmacology : RTP. 2009;55(1):1-5.
- Bilyeu T. Our latest Upgrade: Soluble Corn Fiber 2015 [Available from: http://blog.questnutrition.com/our-latest-innovation-soluble-corn-fiber/.