Tuesday, 16 May 2017

Update: Bananas Re-Tested!


By Shirley Webber & Lyndal McNamara (Research Dietitians)
From time-to-time, we re-test a food tested in the past, to ensure that the information we provide to app users is up-to-date. This is important as changes in agricultural and environmental factors can influence FODMAP levels in food. Our scientific testing methods have also become more advanced over time, allowing us to detect FODMAPs with even greater sensitivity and accuracy.
Our most recently re-tested food was banana. We chose banana in part, because many people had reported discomfort after eating ripe bananas. Our app has since been updated with these new data.

New FODMAP ratings of common ripe bananas versus unripe bananas


Ripe banana




High
(Oligo-fructans)

Unripe banana






Low

Why has the FODMAP rating of bananas changed so significantly?
We know that agricultural and environmental factors influence FODMAP levels in food and believe that the changes in our FODMAP results may reflect this.
From published research we know that plants naturally tend to accumulate fructans in response to environmental stressors such as cold temperatures and drought.(1) Fructans provide plant cells with greater structural integrity, making them more hardy and resistant to damage from environmental changes and disease.(1)

Studies investigating bananas specifically have found that their fructan content increases when they are stored and ripened in cold storage, which is now relatively common practice by supermarket chains to prevent spoilage and guarantee even ripening.(2, 3) Farmers may also be selectively breeding varieties of crops with a higher fructan content, as they tend to be more resilient to pests and diseases.(1)
As our findings have confirmed, simple changes in how we grow or even store food over time can have a significant effect on their FODMAP content by the time they reach consumers. This emphasises just how important it is to test and retest foods to ensure that the FODMAP composition data provided in our app is consistent with the foods currently in the food supply.
To reflect these new findings, we have updated the banana listings in the app and revised the banana recipes. Remember to check the app for this updated information, including serving size information. When you look at the serving size information, you will see that you can still have a small serve of ripe banana (1/3 banana). It is important to remember that if you currently tolerate ripe bananas well, then there is no need to remove them from your diet. Remember, your diet only needs to be as strict as your symptoms require!

References:
  1. Valluru R, Van den Ende W. Plant fructans in stress environments: emerging concepts and future prospects. J Exp Bot 2008; 59 (11): 2905-2916. Shalini R, Antony U.
  2. Agopian R G D, Purgatto E, Cordenunsi B R, Lajolo F M, Paulo U D S. Synthesis of fructooligosaccharides in banana `prata` and its relation to invertase activity and sucrose accumulation. Amer Chemical Soc. 2009.
  3. Fructan distribution in banana cultivars and effect of ripening and processing on Nendran banana. Journal of Food Science and Technology. 2015;52(12):8244-8251.

17 comments:

  1. That is, without a doubt, very sad news!

    ReplyDelete
    Replies
    1. Hi there, if you have been eating bananas with no trouble or symptoms, then there is no need to exclude them from your diet!Remember, the low FODMAP diet only needs to be as strict as your symptoms require :) All the best, Monash FODMAP

      Delete
  2. I really do appreciate that you all re-test food and make updates in the app, but it is SO frustrating for users that there is no announcement in the app when these updates are made to foods that had already been tested. I've noticed multiple foods that have had information updated in the past few months (tomatoes, spaghetti squash, bananas), but there is no notice in the app to draw our attention to these changes. For those of us who have been using the app for a while, we often have green-light portion sizes memorized for our favorite foods, and we don't need to keep going back in to check the food. If you make a change to the information for that food in the app, we'll never see it! Please develop a way to announce which foods have been changed when you do app updates! I know you eventually post about some of these things on the blog, but that is very easy to miss and these notices should absolutely be included directly in the app. Thanks for taking this into consideration. I am grateful for the research you do!

    ReplyDelete
  3. Would be interesting to know whether it makes a difference if they are organic or not?

    ReplyDelete
    Replies
    1. Organic per as should make no difference to Fructan level. There may however be a correlation between these new high Fructan bananas and their use by non organic low cost growers. Fair Trade label may provide an even better guide to older lower Fructan varieties?

      Delete
  4. Good timing with the update! I think ripe bananas have been a mystery trigger for me. I'm going to avoid them for a week and find out.

    ReplyDelete
    Replies
    1. It proved the case for me, just googled this to confirm

      Delete
  5. There are discrepancies between the Fodmap Friendly app results and Monash's results on some things. Does this mean more foods need to be retested? Why do the results differ so much? It is extremely difficult to make quantity choices on foods if you are not sure of how much you can try or whether a food is safe or not. When my stomach is touchy I don't really want to play around and test foods. I find that I cannot reintroduce anything back in or it sets it all off again.

    ReplyDelete
  6. I have a question about the serving size for bananas. I tend to use the weights on the app since I'm in Canada and so many foods are packaged differently. I'm assuming the weight for bananas doesn't include the peel. Is that correct?

    ReplyDelete
  7. If I buy a banana and freeze it before eating, is this OK as long as it is an unripe banana?

    ReplyDelete
    Replies
    1. I was wondering the same thing along with cooking one as well!

      Delete
    2. I also need to know this! Any thoughts Monash!

      Delete
    3. Hi Hazel, Jess and Anne,

      Thank you for your comments. Unfortunately not as the banana will still ripen when frozen

      All the best,
      Monash FODMAP

      Delete
  8. I really appreciate the suggested portions of foods that one may tolerate. There are foods they suggest I can never eat without problems.My mother said I cried when she gave me a bottle when I was a baby. She also fed me small portions like a 1/4 of an orange. I think some of these tolerances one doesn't grow out of. I can only eat a 1/4 of an orange or less. If your body doesn't have the enzymes to digest fructose or lactose,one isn't going to be able eat those foods without problems.

    ReplyDelete
  9. I really appreciate the suggested portions one can eat.I have suffered all my life not knowing the reasons for not being able to eat fruits,vegetables, and grains without difficulty. These digestive issue I was born with, not acquired.

    ReplyDelete
  10. I notice that banana bread is still listed in the recipe list on the app - do you know if cooking banana makes a difference to its oligo-fructan contents? I'm still in the elimination phase so I'm being as careful as possible. Thanks!

    ReplyDelete
  11. Rather than high low, it would be useful if there was a scale rating. I (at age 55) know I cant tolerate garlic, onions, shallots leeks etc unless cooked down. well, those around me can't tolerate me after I eat it. I have had significantly wavering weight and found things like cornflakes make me sleepy. Im trying low FODMAP to see if that helps. So far I'm sticking to mostly protein and sleeping a lot better and have dropped a lot of weight. Doctors have said I appear to be having an inflammatory response but no markers.
    Is there any testing that can be done? Doing it with food is proving difficult.

    ReplyDelete