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    Dr. Peeke
    TCL38 posted:
    I have seen several magazine and/or internet articles lately about how cooking in plastic can/does interfer(s) with weight loss.

    Unfortunately, I have been unable to find the science (I'm a researcher) behind these articles. Can you point me in the right direction and give me your take on this?

    I find it really interesting especially since plastic food containers are manufactured to store, freeze and heat food. And I also have noticed an increase of heat-in-plastic food from vegetables to premade meals.

    Aside from that I spent four years on the diet boards here on WebMD and no matter how much I counted carbs/cals or how much or what type of exercise I did I couldn't lose weight. I have now four years of records weighing and measuring everything and for a time I lost weight at the rate of 1/4 a week despite being perfect. For me the only thing I could "prove" is conventional diet wisdom does not work for me and my body and despite many tear-filled conversations with several doctors no one can explain it to me either. So if there's something to this plastic thing I want to know.

    But as a researcher my caution-this-sounds-like-junk-science detector is flashing.


    Louise_WebMD_Staff responded:
    Interesting Tanya. I hope Dr. Peeke can come up with some science around this--I will also throw this to our content people to see if they have some research pro or con about it.
    ~Louise Senior Community Moderator
    Pamela Peeke, MD, MPH, FACP responded:
    Hi and thanks for your posting. First, to help you understand the role of plastics in cooking, here's a great link to an interview with a Johns Hopkins expert Dr. Rolf Halden on the subject:

    The bottom line is that you need to cook in heat resistant materials like glass and ceramics. Anytime you heat plastic, chemicals are released. Conversely, when you freeze in plastic, this does not occur. When you microwave a packaged food, try to remove it from the plastic container and place in a dish or glass or ceramic container instead.

    Next up, there is no current peer reviewed evidence that cooking in plastic containers interferes with weight management.

    I hear your frustration Tanya. So long as you have been thoroughly assessed by a medical team that has looked at your thyroid function and any other metabolic issues you may have (polycystic ovarian syndrome is one missed frequently), then I would highly recommend that you sit down just once with an excellent registered and licensed dietitian and really study your nutritional regimen. You need to have your eating as well as exercise plan customized to your age, height, weight, body fat %, medical status and lifestyle.

    Let us know if we can further help you.

    Good luck, Dr Peeke
    TCL38 replied to Pamela Peeke, MD, MPH, FACP's response:
    Thank you Dr. Peeke but that link is not for the Dr. Halden interview.

    What I am looking for is maybe a step or so above "consumer" information. My research career started as a medical researcher for a national company. I read journals from JAMA and Lancet all the way down to publications like The Grey Sheet. So I'm looking for the actual science.

    I am rather curious about this because if it's "true" then how are food companies "getting away" with marketing food such as vegetables in "steamer" bags.

    And of course I am interested for my own benefit. I am disabled so plastic is my friend. It's light weight and when I drop it, it doesn't break.

    I do have several metabolic issues i.e. hypothyroid and PCOS. And at this point in my life oh to be able to afford a dietician. My medical costs are 1/3 of my total income which ends up being less than what most families our size spend on groceries.

    Of course all my docs want me to lose weight and I just look at them and say you fix my broken metabolism so I can lose weight and I'll live the rest of my life with these medical conditions and not utter a peep about them.

    I used to box squat over 200 pounds, run a 7 minute mile and I could use a bandana for a belt. And now I gain weight for no dietary reason. I just can't figure it out. And if plastics is part of the problem then I'm going to have to figure something out but with my current health I am not going to risk injury or pain without a verifiable trail of good research.


    Jis4Judy replied to TCL38's response:
    Tanya all I heard from articles etc is when you use plastic in a microwave it leaches into the food and can cause problems with health endoctrin problems whatever that is,,It is Ok to store in plastic but not microwave with it ,,,just avoid heating with plastic use a glass lid or something to cover things while heating..
    Hugs Judy:)
    Jis4Judy replied to Jis4Judy's response:

    this article explains what might happen

    Hugs Judy:)
    TCL38 replied to Jis4Judy's response:

    That's what I've heard too but I can't find the science behind it.

    A good example of why I am so curious is I have found I actually like edamae/soybeans. My daughter convinced me to give them another try and I loved them. I buy a frozen brand that has 3 servings to the package. It's one of the steam bags where you just toss it in the microwave and cook it in the bag. I split it between the two of us (my son won't even look at and no clean up! This is the only product I buy like this right now but some of the other steam-in-bag food looks interesting. So if cooking in plastic is bag, what's up with all this new products?

    And I have cooked in plastic for a long time and more so recently now I am disabled. If it's really bad I will figure something else out but I would like to see the science. You know me always looking for the

    Jis4Judy replied to TCL38's response:
    sometimes if we wait to hear the science behind things that are rumored to be bad for us we may have so much damage done that it is not repairable like so many people smokeing the science wasn;t there for a long time it really made many people sick...I heard that healthy eating was good for my body and embraced it because it gave me hope that I could control this area and heal myself . I am now the science proof for me to continue along my proven path.. I made my own body the science project ,,I am happy with my resuts but it isn;t a perfect science with lots of people ....or anything..
    I wish you health Tanya
    Hugs Judy:)
    Jis4Judy replied to Jis4Judy's response:
    another link
    Pamela Peeke, MD, MPH, FACP replied to TCL38's response:

    I think you're getting hung up on this subject when the real issue is to prioritize eating whole foods in heat resistance containers if you're microwaving especially. Steam fresh vegetables and I avoid the plastic bagged veggies. You ask a lot of "why's" and the reality is that it's a moot point. We know that cooking in glass and ceramic is the way to go so let's just do it.

    As a scientist, sometimes we have to just go with common sense and not wait for the best peer reviewed research. Go fresh and stick with whole foods. That's the bottom line.

    Dr Peeke
    TCL38 replied to Pamela Peeke, MD, MPH, FACP's response:
    I respectfully disagree Dr. Peeke.

    For my personal situation, "common sense" as you call it is to use plastic when I cook in the microwave. More often than not a filled ceramic cereal bowl (like the kind you would find in sets of dishes) is too heavy for me to lift because of serious nerve problems, a disk herniation and other medical problems. And since my microwave is one of those mounted-in types lifting anything above my shoulder height can be very dangerous so the lighter the better. My "common sense" also involves not dirting a pan and the steamer basket just to do some veggies since I have trouble washing dishes even with the dishwasher. I also can't use knives most of the time to chop something as "soft" as a red pepper.

    And thank you but I do focus on whole foods when I can. However with my medical conditions sometimes it's a can of soup or nothing. If heating that soup up in plastic is really a problem, then I'll be fat forever. Before my medical conditions hit me, four years of a whole foods, controlled diet and appropriate exercise didn't make me skinny and I rarely if ever cooked in plastic so I just don't see a smoking gun here.

    But thank you for taking the time to try to answer my question. I'll keep looking.

    jg625 replied to TCL38's response:
    When plastic is heated in a microwave, it emits estrogen-like substances which can leach into the food. Doesn't sound horrible at first however we are an estrogen-dominant society. For women, (but men are also affected) this can be caused by drops in progesterone (as early as in our 30's) which opposes estrogen, so so many environmental factors such as pesticides and other chemicals which contain estrogen-like compounds as well as our commercial food supply (hormones and antibiotics added, we know that corporate America is most concerned with their bottom lines, not our ultimate health, so self education is important to minimize our exposure to chemicals that do not serve our best interests), and yes even soy/edamame which I too love, but moderation here is the key because soy contains plant estrogens! Soy has also been shown to inhibit thyroid function, so if you already have thyroid issues, you may want to be careful. Too much estrogen can cause weight gain/difficulty losing weight. It is a bit of a Catch 22 though, body fat can produce estrogen...too much estrogen can add pounds....vicious circle!! You may want to check out a site I've found helpful...Natural Hormone Institute, and a book you'll find there "From Hormone Hell to Hormone Well." Balance is the key though, which also means eating whole foods, minimizing our exposure to toxins, 8 hours of sleep per night and regular exercise... 45-60 minutes at least 5 times per week. I empathize, your struggles are similar to mine, hope you find this helpful. Best wishes and good luck! joanie
    jambajuice replied to TCL38's response:

    First off, allow me say, how sorry I am for your ailments. It must be very difficult for both you and your children. I wish you healthier days, ahead. Nevertheless...

    We are products of what we believe...

    Like the movie, "Inception". Once a thought is planted in our minds and taken root, it becomes a truth...

    You have the following "truth"...

    You are a researcher, yet, you believe you fall outside the natural laws of physics and thermodynamics. You are convinced that calories consumed and calories burned are not accountable in your body.

    Yet, you will be believe a scientific study that says it is (or is not) perfectly safe to eat food heated in plastic from microwave?


    We achieve what we believe and we fail when we doubt ourselves and place obstacles in our path...

    If calories in and calories out do not apply to you, there's a great big gorilla in the room, if you know what I mean...Cooking in plastic is a flea, in comparison.

    Not a truth (or criticism); just an opinion...That's all...
    shimmering responded:
    Well there isn't a lot of research or not many expert reviews on the topic. Also there is so much hoaxes going around, that its really difficult to believe what is the truth.
    But there are so many products that have been proved to be harmful, after many decades.
    It is a scientifically proven fact that plastic does leach chemicals into food when heated in a microwave. Though it is said that only some kind of plastics leech "harmful chemicals", especially carcinogens.
    So it is still a fact that there will be some chemical leeching with every type of plastic. But what is considered harmful keeps changing from time to time.

    Not so long ago, fertilizers were supposed to be the best thing that ever happened to farming. Today everything we eat is polluted because of these safe to use fertilizers. But today we know better.

    What I want to say is TLC38, that isn't it better to not to use plastic, or to limit its use as much as possible, when we still know that it might not be so good for your health.

    I do understand your position and maybe you can use some of the lighter versions of glass, like corelle, which are much lighter than other glass utensils and also lighter. Also maybe some of the steel containers. Also maybe you can cook once a week or work something out like that so that you won't have a ton of dishes to wash everyday.

    But if its extremely impossible for you to use alternatives, then the best thing you can do is to use plastic, that is specially made for cooking, which says its microwave safe and not use the flimsy cheap ones, or the ones that come with the supermarket food.

    Weather you use plastic or not is the choice that can be best made by you.
    freecard replied to jambajuice's response:
    Calories in....Calories out probably does not apply to most of us. Recommend you read Gary Taubes: Good Calories, Bad Calories.

    Resistant weight loss has many causes, and the advice regarding a complete work up with comprehensive metabolic and hormonal analysis is sound. Heavy metals, in addition to endocrine "disruptors" have also been reported to be a cause of resistant weight loss, and this is not a "typical" analysis for most doctors.

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