Research Review: Healthy french fries?

Research Review:
Healthy french fries?

By Helen Kollias, Ph.D.


Does adding something potentially good to a junky food make the junky food better? Does it turn French fries into broccoli?

Since you’re probably in the middle of figuring out your New Year resolutions, what would you do if you found out your favorite junk food was even worse for you than you thought?

Yes, it’s hard to believe, but fries and chips (or chips and crisps for our friends in the UK) are worse for you than we thought.

Before I tell you why they’re worse for you, what are you going to do now?

Will you add “stop eating fries and chips” to your resolutions?

Or will you look for a loophole — you know, try to add something that would make them less bad and eat away?

Sounds strange to try to make something less bad for you instead of just… not eating it!

Well, a couple weeks ago I heard on the radio that Health Canada (the Canadian equivalent to the Food and Drug Administration [FDA] in the US) was proposing to allow food manufacturers to add an anti-cancer drug to chips and fries to make them safer [1].

Don’t misunderstand — they’d still have little nutritional value, nearly no protein, lots of saturated fat, and lots of carbohydrates, but they’d be acrylamide free!


Acrylamide & cancer

Many of you probably know this, but back in 2002, the Swedish National Food Administration reported that a chemical called “acrylamide” was in fried foods and baked food [2 & 3].

Foods with the highest amounts of acrylamide were French fries and potato chips, but other foods like breads, cakes, cookies, cereals, coffee and cocoa have some acrylamide in them too.

Finding acrylamide in food was big, because it’s a probable carcinogen, which means that it likely causes cancer in people. However, 6 years later we still don’t know for sure.

What researchers do know for sure is that acrylamide causes cancer in rats [4].

What is acrylamide?

Acrylamide is a chemical that is made when starchy low-protein food (like potatoes) are cooked at a high temperature (over 120⁰C or 248⁰F).

Foods don’t have any acrylamide in them until after they are cooked; it’s the process of cooking that makes the acrylamide.

Acrylamide is not all bad: it’s made and used for other things, like to separate proteins in molecular biology and for wastewater treatment.

Asparaginase — the acrylamide blocker

Asparaginase is the anti-cancer drug Health Canada is thinking of allowing as a food additive in order to reduce how much acrylamide is made during the cooking of fries, chips and other foods.

By the way, I want to clear up this idea of asparaginase as an anti-cancer drug.

Asparaginase is used in cancer treatment, but I wouldn’t call it a drug. It’s actually an enzyme that is in bacteria, plant and even animals (guinea pigs, for example).

All asparaginase does is convert asparagine (the amino acid) into aspartic acid (another amino acid) [5].

Asparagine is important for cells to survive and grow. With no asparagine, cells die [6].

Certain cancerous tumour cells can’t make much asparagine, but normal cells can. Thus, asparaginase gets rid of any asparagine so cancer cells die. Normal healthy cell have no problem, because they just make more of their own and stay healthy.

Thus, in theory, adding a cancer-preventing agent to a cancer-causing food should, I guess, cancel things out.

Research question

After hearing that the food industry wants to add asparaginase to food I wanted to know two things:

  1. How could they do it; and
  2. Would it work?

For this week’s review I take a look at a study that figures out how to add asparaginase to French fries, and what happens when you do.

F Pedreschi, K Kaack, K Granby. The effect of asparaginase on acrylamide formation in French fries. Food Chemistry, 2008. 109:386-392.


This paper is basically cooking meets science.

Half the paper describes how the researchers cooked fries in scientific detail, and the other half figures out much acrylamide was in the different fry recipes.

Just so you get an idea of the descriptions, here is one of my favourites: “Strips of the cross sections of 0.8 cm X 0.8 cm2 were cut from the pith of the… potato tubers.” (In other words, they cut potatoes into French fries.)

The researchers had five different recipes for the fries:

  1. Control fries – basically how most people make fries
  2. Blanched fries – the fries were quickly boiled at 75⁰C for 10 minutes
  3. Blanched and then asparaginase treated fries – blanched fries soaked in asparaginase for either:

a) 20 minutes (at 40⁰C)
b) 10 minutes (at 50⁰C)
c) 10 minutes (at 60⁰C)

All five fry groups were then deep fried and analysed for asparagine, glucose and acrylamide.

In theory, the fries treated with asparaginase will have less asparagine (since asparaginase breaks down asparagine) and these fries would also have less acrylamide.


The results came out how you’d expect:

  1. Fries soaked in asparaginase had less asparagine and acrylamide than the control fries.
  2. Fries soaked in asparaginase the same amount of glucose as the control fries.

Remember that frying the potatoes is what makes the acrylamide, so before the potatoes were fried they had no acrylamide.

Interestingly, blanching fries before you soak them in asparaginase gives you even less acrylamide and even fluffier fries than not blanching them; and soaking the fries for 20 minutes at 40⁰C was the best treatment for reducing acrylamide by 60% compared to the controls.


If a food manufacturer wants to add asparaginase to French fries all they have to do is blanch the fries, soak them in asparaginase for 20 minutes at 40⁰C, freeze them and then send them off to a restaurant or grocery store for the consumer to deep fry them – that’s it.

Thus adding asparaginase seems to be relatively easy for food manufacturers.

Not only is adding asparaginase to fries easy, asparaginase actually works to lower the amounts of asparagine and acrylamide in fries. Then manufacturers could add “now with 60% less acrylamide” to the label that already has “trans fat and cholesterol free”.

Again, from the food manufacturers’ point of view to have acrylamide-reduced fries is financially a good idea, and since it’s easy to do, why not?


But doesn’t this idea of adding something to make something bad safer remind you of something?

Doesn’t it remind you of adding filters to cigarettes or having light cigarettes? And we all know how that turned out.

Personally, I don’t think that Health Canada or any other government association should be okaying additives to any food, especially junk food. Next there will be beer with vitamin C and soda pop with insulin.

This is just another example of making a simple solution — stop eating chips and fries — into something much more complicated: We’ll add a genetically modified enzyme to the fries and make everything better. Keep chowing down those fries, folks!

Here’s a resolution for you — stay away from new and improved trans fat-free, acrylamide free chips, fries and cookies; and stick with old and unchanged blueberries, broccoli and kale.

Joan Crawford and her mild Camels endorse new smooth-smokin’, acrylamide-busting Doritos!

Passionate about nutrition and health?

If so, and you’d like to learn more about it, consider the Precision Nutrition Level 1 Certification. Our next group kicks off shortly.

What’s it all about?

The Precision Nutrition Level 1 Certification is the most respected education program in the field. It gives you the knowledge, systems, and tools you need to really understand how nutrition influences a person’s health and fitness.

Developed over 15 years, and proven with over 100,000 clients, the Level 1 curriculum stands alone as the authority on the science of nutrition and the art of coaching.

Whether you’re already mid-career, or just starting out, the Level 1 Certification is your springboard to a deeper understanding of nutrition, the authority to coach it, and the ability to turn what you know into results.

[Of course, if you’re already a student or graduate of the Level 1 Certification, check out our Level 2 Certification Master Class. It’s an exclusive, year-long mentorship designed for elite professionals looking to master the art of coaching and be part of the top 1% of health and fitness coaches in the world.]

Interested? Add your name to the presale list. You’ll save up to 33% and secure your spot 24 hours before everyone else.

We’ll be opening up spots in our next Precision Nutrition Level 1 Certification on Wednesday, October 2nd, 2019.

If you want to find out more, we’ve set up the following presale list, which gives you two advantages.

  • Pay less than everyone else. We like to reward people who are eager to boost their credentials and are ready to commit to getting the education they need. So we’re offering a discount of up to 33% off the general price when you sign up for the presale list.
  • Sign up 24 hours before the general public and increase your chances of getting a spot. We only open the certification program twice per year. Due to high demand, spots in the program are limited and have historically sold out in a matter of hours. But when you sign up for the presale list, we’ll give you the opportunity to register a full 24 hours before anyone else.

If you’re ready for a deeper understanding of nutrition, the authority to coach it, and the ability to turn what you know into results… this is your chance to see what the world’s top professional nutrition coaching system can do for you.


Click here to view the information sources referenced in this article.

Spots open October 2nd — don't miss out! Get on the Precision Nutrition Level 1 Certification presale list today.

If you're interested in the Level 1 Certification, we strongly recommend you join the presale list below. Spots are limited and open just twice per year.

We'll send you more info about the program, and give you the chance to register 24 hours early — and save up to 33% off the general price.