Toxic alert: 5 foods you should never heat or reheat

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stove-top-cooking(NaturalHealth365) Leftovers for dinner is just a way of life these days.  But, can these meals ever be toxic?  After all, they are easy, quick and right there in the frig, so why not eat it?  The answer may surprise you.

In reality, certain foods – when heated or reheated – can threaten your health.  Therefore, knowing about them may just make you consider eating them cold (or not eating them at all).

Avoid these toxic heating and reheating techniques to protect your health

Before we get to specific foods whose toxicity levels change when heated or reheated, let’s go over the basics you will want to keep in mind to avoid cooking-related toxins in general:

Ditch the microwave.  Today, 90% of all American homes have a microwave oven and remain unaware of the risk.  I know how convenient cooking with a microwave can be.

However, a study conducted by the University of Vienna almost thirty years ago linked microwaving to nerve damage and lowered kidney function. Other studies have connected it to a drastic reduction in liposome activity, needed to inhibit harmful bacterial growth.

Never use saran wrap, plastic ware, or Styrofoam to reheat food. If you must use the microwave, NEVER use containers or lids that are made of plastic in any form. Plastic cookware and coverings release a variety of harmful substances when heated.

Two of the most toxic substances are polyethylene terephthalate (PET) and biphenol A (BPA).  BPA is a xenoestrogen that has been directly linked to breast cancer.  Styrofoam contains styrene, which the International Agency for Research on Cancer has deemed a “probably cancer agent.”

Don’t use Teflon cookware. The main ingredient in most non-stick surfaces is polytetrafluoroethylene (PTFE), which has been labeled as “likely to be carcinogenic to humans” by the EPA.

Dupont’s Teflon also contains PFOA (C8). Studies show a correlation between PFOA and immune system issues, thyroid issues, pancreatic cancer and breast cancer. Approximately 98% of the population of the U.S. has some level of non-biodegradable PFOA in their bloodstream.

Editor’s note: Discover a safe alternative to toxic cookware.

Stay away from aluminum foil. Using aluminum foil as a cover or container for heating foods (and using aluminum cookware in general) releases this substance into the food. Aluminum exposure has been linked to neurological issues and long-term exposure has been linked to Alzheimer’s, autism and ADHD.

These 5 foods should never be reheated under any circumstances!

1. Veggies with high concentrations of nitrates: Celery, carrots, beets, spinach and especially turnips have high amounts of naturally-occurring nitrates within them. Nitrates from veggies are actually vital nutrients our bodies need for everyday functioning.

When we eat these veggies raw, the bacteria in our mouth convert these nitrates into nitrites, which are then stored in the cells until they are needed in the form of nitric oxide, a natural anti-inflammatory that can calm blood vessels and help to increase blood flow.

The heating process converts nitrates in veggies into nitrites before they enter your mouth; each time you reheat them, they become a little more toxic. Because of this, the best way to eat celery, carrots, spinach and beets is organic, raw and as fresh as can be!

2. High-protein foods: Eggs, chicken, and even mushrooms are all protein powerhouses but these proteins begin to deteriorate as soon as you cook them. The protein composition of chicken in particular, which contains a higher protein content than red meat, changes when it goes from cold to hot the second time around. All this puts added strain on your digestive system.

The best bet for these kinds of foods is to only cook up what you think you will consume in the first sitting. If you must reheat chicken, make sure it is very hot through and through. Eggs and mushrooms in particular are vulnerable to microorganisms. It is best to never reheat them at all.

3. Rice: Cooked rice of any variety stored in the frig improperly may be at risk of developing bacterial spores that can cause food poisoning. This is especially true if the rice is left to sit at room temperature because it can lead to rapid spore multiplication which can cause severe digestive upset and even poisoning. If you do reheat rice, be sure it has been stored properly in an air-tight container.

4. Potatoes: Potatoes should be avoided or eaten in moderation if one is on a healthy breast protocol because of their high sugar content. That being said, cooked potatoes do contain vital nutrients such as vitamin B6, potassium and even vitamin C. When cooked potatoes are left at room temperature, however, or are slow-cooked a second time, they can turn toxic. Warm temperatures can promote the growth of botulism in potatoes so always refrigerate them immediately and throw away anything that has potatoes in it after a couple of days.

5. Oils: Certain oils have very low tolerance to heat and will even turn carcinogenic the first time you cook with them. These include grape seed oil, hazelnut oil, and flax seed oil. When you reheat these kinds of oils a second time, they will become rancid. Never use these oils for baking or cooking. Instead, consume them fresh, drizzled on top of a salad, steamed veggies or organic meats.

Consuming fried foods when dining out is never recommended under any circumstances. This is because most restaurants use the same oil all day for their frying. A recent study found that the toxin 4-hydroxy-trans-2-nonenal (HNE) forms when common restaurant oils, such as canola, corn, soybean and sunflower, are reheated. HNE has been connected to a higher risk of heart disease, stroke, Parkinson’s Disease and cancer.

Follow these guidelines (or, even better, reach for the goal of getting most of your nutrition from fresh, organic foods) and you will be on your way to significantly reducing your toxic load. And remember – when it doubt, throw it out!

About the author: Dr. Veronique Desaulniers (“Dr. V”) is a best-selling author and specialist in Chiropractic, Bio-Energetics, Meridian Stress Analysis, Homeopathy and Digital Thermography. After 30 years in active practice, she decided to “retire” and devote her time to sharing her personal, non-toxic Breast Cancer healing journey with others. Her years of experience and research have culminated in “The 7 Essentials™ “, a step-by-step coaching program that unravels the mystery of healing the body. Her website and personal healing journey have touched the lives of thousands of women around the globe. To get your F.R.E.E. 7-day mini e-course and to receive her weekly inspiring articles on the power of natural medicine – visit:


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  • Noreen Burke

    It is common practice to wrap potatoes in tin foil when you bake them. My family always did this. I am the only one who wouldn’t even consider it. When they come for dinner at my house they complain the potato skin is too crispy.

  • Leona Hayes

    When we go to picnics not only does the food stay out in the sun, it is protected by tinfoil. Going by this article this is not a healthy practice.

  • Fern Leroy

    With all these restrictions I will be serving a lot salads for dinner. Most of the food we eat is from fast serve deli counters. Being a working mother this is a time saver.

    Now, that I read the article I can’t continue to that in good conscious. Deli meals are being heated all day long and the same probably goes for restaurant soups and stews.

  • James

    So what’s a good substitute for a microwave?

    • ahuxley

      A macrowave.
      But you can only nuke reeeaaaly big things in it…

    • Emily27

      We use those bamboo baskets with a lid to reheat our individual plated dishes. We place the bamboo in a wok filled with a little bit of water. We never missed the microwave.

  • CancerFighter

    The chicken information seems contradictory. “The protein composition of chicken in particular, which contains a
    higher protein content than red meat, changes when it goes from cold to
    hot the second time around.” but then it goes on to say…”If you must reheat chicken, make sure it is very hot through and through.”

  • d-dectiri

    Lousy article. No substantiating data. How can anybody take this seriously.

  • you are correct on the potato and inulin but it used to be the potato salad made with mayo and was due to the eggs- taken to a picnic on a hot summer day and then kept as left overs…. guess some got salmonella from it.

    and microwaves alter the protein of the food by the way they heat from the inside out, so if you want poor protein use the microwave.

  • never mind the article 😉 well sort of
    all my cooking life i have made more potatoes than for one meal and more rice as well. Hardly ever do i store the left over/extra in the fridge! for one because it is still too warm at the time. It has sat out over night plenty of times, potatoes for some times 2 days – we like to eat them cold/room temp with a bit of salt for a snack. Granted that happens more in the cold time of year and the kitchen is not overly warm unless i bake and cook however, per this article we should have been sick many times for “spoiled” food – or we are just used to it???

  • tweak and adjust, no need to unravel your whole life of cooking 🙂 per this article i should be dead!

  • I was following on 1 and 2 by 3 and 4 I figured I should have died multiple deaths by now. The fried and oil is mute for me, don’t do that any way, ha, scored one.
    No way we will not have left over stew with veggies in, but then we heat on the stove on low heat.

  • David_R59

    Just a little more information on the lowly spud:
    Organically home-grown potatoes are light-years away from a potato grown on the average chemical farm. Home grown-organic have a much lower level of sugar and a much higher level of protein. The extra minerals make them taste better too.
    If you like your spuds but worry about sugar levels then it’s time to dig up some of that “perfect lawn” and put in a year’s supply of storable potatoes.