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Why is frying food unhealthy?

Does anyone know why frying food is less healthy than broiling or baking?

Well obviously deep frying chicken in a batch of oil is bad for you. But let's say you fry salmon in a couple tablespoons of olive oil vs. baking the salmon in foil with a couple tbspoons of olive oil.

Why is one technique considered less healthy than the other?

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  1. I don't even buy your assertion that deep-fried food is by definition "bad for you."

    1 Reply
    1. The only jfood can think of is you eat more of it since it is so much better....Nah!!!! Yum.

      1. If we try to use the oven for this, does this also considered unhealthy?


        1 Reply
        1. re: janetvelasquez80l

          you mean to reheat or warm the fried food!!!?

        2. For me the reason I think a lot of fried food -- especially fast food or restaurant food -- is unhealthy is because the oil has often been overheated or heated too long and the oil breaks down into "undesireable" components we don't really want in our diet.

          "Healthy" fried food is possible, primarily when you do it at home and use the right oils and temperature. But even at that, it can add calories! But hey, we can't limit our diet to tap water, can we? '-)

          3 Replies
          1. re: Caroline1

            This is what I've understood to be the case, too. The undesirable component of most concern is trans fats, when the oil has been used beyond the point where it should. I'd also like to add that there are restaurants who are more responsible than others with frying food. They are few and far between, but I've eaten at a few. It's a special pleasure to enjoy food fried in olive or rice bran oil, which have a delicacy and flavor you don't often find. I'm of the mind that fried food is a treat, not an every day indulgence.

            1. re: amyzan

              I'll have to look more into this, but off the top of my head, I thought that trans fat came from the process of partially hydrogenating oil. Overheating/overusing oil does produce undesirable compounds, but I'm not sure trans fat is one of them. ...

              1. re: 4Snisl

                You're right. Overheating or using oil too long does not produce trans fats, BUT....! Cooking food in that contains trans fats such as battered foods in which hydrogenated shortening or margarine is an ingredient will leach trans fats into your cooking oil, and then into any foods that are subsequently cooked in that oil. I don't buy anything with the word "hydrogenated" anywhere on the label!

          2. To address this I think you need to be a bit more precise. While the term "fry" in popular usage can include that type of cooking which uses only a bit of oil in the bottom of a pan, in industry and most food journalism usage that is "sauteing," or sometimes "pan frying;" the term "frying" refers specifically to what at home is called deep frying.

            So, sauteing isn't usually so bad. To follow your example, doing a piece of salmon by "pan frying" in a little olive oil oil probably isn't much, if at all, less healthy than baking the salmon.

            Deep frying on the other hand, the process referred to as "frying" in industry jargon, often is indeed worse for you, but as others have noted, it ain't necessarily so. It can be reasonably OK if the coating is correct, the oil is correct and fresh enough, and the temperature is correct. Unfortunately, in the real world one or more of these criteria is typically violated.

            1. Fried food is not "bad" for you...Bad fried food is however.

              1 Reply
              1. re: Uncle Bob

                Touché! And I don't just say that 'cause you have such a cool name. ;-)

              2. Pretty simple I think, that salmon is going to keep a lot of the oil attached to itself, so you get added fat and calories. Salmon already has plenty of healthy fat in it, doubt the extra from the olive oil is doing you any good. Put that same piece of salmon in the over on some non stick aluminum foil, and you get none of the added fat or calories from the oil.

                12 Replies
                1. re: Rick

                  I always thought maybe there was some type of unhealthy chemical reaction happening when you fry food vs baking.

                  French fries for instance produces carcinogens when deep fried at high temps.

                  1. re: david t.

                    Acrylamide is found in all kinds of food cooked at high temperatures not just frying,


                    1. re: david t.

                      Not all deep fried foods produce carcinogens ..... According to this article, it's healthier and safer to eat deep fried foods with the exception of potatoes, than grilled or BBQed


                      1. re: Cherylptw

                        Which article? There are 24 cited in that wikipedia entry.

                        1. re: KTinNYC

                          Bottom of the page, articles 7-11 corresponds to the info on the page for that link

                          1. re: Cherylptw

                            I'm completely lost. Maybe I'm just dense but how does any of this have to do with your point?

                            "Cooking food at high temperatures, for example grilling or barbecuing meats, can lead to the formation of minute quantities of many potent carcinogens that are comparable to those found in cigarette smoke (i.e., benzo[a]pyrene).[7] Charring of food resembles coking and tobacco pyrolysis, and produces similar carcinogens. There are several carcinogenic pyrolysis products, such as polynuclear aromatic hydrocarbons, which are converted by human enzymes into epoxides, which attach permanently to DNA. Pre-cooking meats in a microwave oven for 2–3 minutes before grilling shortens the time on the hot pan, and removes heterocyclic amine (HCA) precursors, which can help minimize the formation of these carcinogens.[8]

                            Reports from the Food Standards Agency have found that the known animal carcinogen acrylamide is generated in fried or overheated carbohydrate foods (such as french fries and potato chips).[9] Studies are underway at the FDA and European regulatory agencies to assess its potential risk to humans. The charred residue on barbecued meats has been identified as a carcinogen, along with many other tars.

                            Dr. T. Colin Campbell argues in The China Study that the milk protein casein, found in milk and many prepared foods, is also a carcinogen.[10] However, independent studies report that casein and other milk proteins protect against cancer.[11]"

                            1. re: KTinNYC

                              but certainly there is a difference between swallowing carcinogens, placing them into a system that was designed/evloved to break down food as opposed to inhaling it into lungs that are supposed to be exposed primarily to clean air. No doubt inhaling bbq could be hazardous to your health.

                              1. re: KTinNYC

                                The OP asked what why fried foods was unhealthy and that he'd read that fried foods contained carcinogens And I found that per my link that there is more carcinogen in other foods than in fried foods. The link was a reference. That's my point, which I didn't realize was hard to understand.

                                1. re: Cherylptw

                                  I don't know but I think you might have misread both the OP and the part of the wikipedia article you cite. Nowhere did the OP mention carcinogens and as far as I can see the article makes no judgment as to what is healthier, grilling or frying.

                                  1. re: KTinNYC

                                    You're right, I concur that the OP didn't mention carcinogens. My mistake; davidt. did and if you notice, I was responding to his post. In any event, the article talked about carcinogens in deep fried potatoes (chips & fries) it didn't say anything about other fried foods carrying a unhealthy amount of carcinogens.

                                    The purpose of the article was not to compare frying vs. grilling. The purpose was to inform about carcinogens and the sources thereof. Nowhere did it say that most fried foods with the exception of those listed were unhealthy but it did say grilling was. Which takes me back to my reason to post the link. Seriously, it's not that hard to decipher the article & the connection to my comment.

                                    1. re: Cherylptw

                                      "In any event, the article talked about carcinogens in deep fried potatoes (chips & fries) it didn't say anything about other fried foods carrying a unhealthy amount of carcinogens and I thought it would be informative to know that grilling was more hazardous to frying foods."

                                      Please cite the part of the wikipedia entry that stated that one method of cooking was more hazardous then another. I may need baby steps to understand.

                                      1. re: Cherylptw

                                        You should reread your link and your posts and maybe you can see the disconnect. There is no evaluation of how any method of cooking is more "healthy" then another.

                    2. different but related: why is pizza considered this iconically bad-for-you food, when it's really just bread, cheese and vegetables/meat ..exactly like most sandwiches? because there's an anti-deliciousness conspiracy.

                      1 Reply
                      1. re: eeejo

                        Pizza is "bad for you" mostly because it's caloric and then partly because the cheese and oil can have saturated or trans fats and then when you add in pepperoni it's more of that. Yes, it's bread and cheese but people seem to think it's low calorie and it isn't. A normal large cheese pizza is about 2400 calories so cut into 6 pieces that's 400 per slice. People often down 3 slices - even at 8 slices per pie that's 900 calories - and a quick "snack" of a slice is like eating most of a big muffin.

                      2. It's only the calories if you're not using an oil with saturated or trans fat. Frying partially replaces water in the food with oil.

                        It's funny that "confit" has become a big word when it's really a method of doing the same thing as frying - replacing the water in the food with fat - but done slowly as a form of poaching.

                        8 Replies
                        1. re: lergnom

                          Fried properly the water in food is not "replacing the water". The water in the food boils in the hot oil, with the pressure of the boiling water keeping the oil from getting into the food. Improperly fried food is oily properly fried food is not.

                          1. re: KTinNYC

                            Well, sometimes deep-frying adds oil. Not necessarily a lot, but some.

                            For example, the amount of oil left in the pan after making a batch of french fries is less than the initial amount. You still have to figure out whether the amount of fat added by the frying process is more or less than the amount you might add (in the form of butter, sour cream, cream, etc.) to a baked potato or a batch of mashed potatoes, but there's no doubt that french fries are higher in fat than raw potatoes.

                            On the other hand, when I make fried chicken using a full 1-quart bottle of vegetable oil, the amount of oil left over is significantly more than the bottle will hold. To the extent that the chicken absorbs any cooking oil, that amount is more than offset by the amount of fat rendered out of the bird. So fried chicken (my fried chicken, at least) is **lower** in fat than raw chicken.

                            1. re: alanbarnes

                              Holy sh&t! Fried chicken is practically health food!. I knew I was on to something!

                              You are, of course, right. But the fat left on food is not significantly more then what would be used if one was to saute the same food. My response was incomplete but I just wanted to refute the point that somehow all water content was replaced by oil.

                              1. re: alanbarnes

                                <"So fried chicken (my fried chicken, at least) is **lower** in fat than raw chicken.">

                                I'll be right over....

                                1. re: alanbarnes

                                  this post reminds me of those old Crisco commercials where they used to pour the oil out into a measuring cup or something to show how little was actually absorbed.

                                  1. re: alanbarnes

                                    A lot of people would not eat the skin on a raw bird : >)) or on a bird that was baked. More likely to peel it off compared with fried chicken where you are eating it because of the skin.

                                    I have often taken notice of the amount of fat used in frying say potatoes or coating them with oil and oven roasting. Assuming some of the oil is atomized in the frying process, evident from the hood clean up after, I'm pretty sure I use less oil in deep frying than in oven roasting. But oven roasting has the appearance of being healthier.

                                    1. re: alanbarnes

                                      are you measuring hot oil because oil expands when it's heated

                                      1. re: chocabot

                                        Nope. Room temp coming out of the bottle, room temp going back in.

                                2. I don't deep fry, but isn't it true that if you fry at too low a temperature, more oil gets sucked into the food you're frying? Help me out experts!

                                  1 Reply
                                  1. re: MsDiPesto

                                    True indeed. Too low a temperature and you get soggy, greasy food. The right temp and food comes out light and crisp.

                                  2. My understanding is that if the oil is not hot enough, instead of the boiling liquid in the food item keeping any excess oil out, the breading on the item will start to absorb the oil, and if you are eating oil, you are eating fat. So incorrectly fried (breaded) foods will have a higher fat and calorie content. My guess is that these experts who make those "rules" are assuming that the people they are writing for are not going to fry their foods at a properly high temperature. If you are somewhat unfamiliar with cooking in general, and frying specifically, it's not so hard to fry at too-low of a temp for fear of over-cooking the outside/undercooking the inside, and ending up with a really greasy product as a result (I've been there. I didn't want the breading to over-cook and end up with raw insides. Have learned since then)

                                    1. Fried food gets such a bad reputation... Doesn't the healthiness depend on the food that is being fried? Like using a dinner roll to eat sauce or gravy left on the plate, breading soaks up frying grease. For salmon, it's no healthier to bake with a crust of butter or mayonnaise (as my roommate used to do!) than to fry in a few drops of olive oil.

                                      There is also a difference between frying in mostly unsaturated fats, such as vegetable oil versus lard, which is solid at room temperature. When food is fried in lard, the fat will solidify instead of leaching out before you eat it.

                                      1 Reply
                                      1. re: Cookiephage

                                        Maybe so, but it sure does taste good!!

                                      2. Food that is fried in fat at the proper temperature soaks up very little excess fat. Unfortunately, fast food frequently falls short, and is loaded with fat. Does anyone think we need this, all concerns about carcinogens aside? Americans are fat, and it's killing us. Treat fried food as a once-a-month treat, and you will be doing yourself a favor.

                                        As I was leaving the mall yesterday after having my hair cut, I was offered a sample of Chick-fil-A fried chicken. That one bite was so laden with salt and fat, that it killed my appetite for hours. Nasty!

                                        1. Not a lot I can add, other than to point out that WHAT you're frying makes a big difference. Starches can easily suck up a lot of fat, and the looser and more open their texture, the more this happens. Properly-fried potatoes still suck up fat, but the larger you cut them, the less they'll take on. (And also, the less delicious and "fried" they taste -- to me, anyway. Some people prefer steak-fry-size potatoes.)

                                          When you fry bread for croutons, for example, or when you have a batter or breading that's very craggy such as panko, you add lots of surfaces for fat to penetrate.

                                          Proteins absorb less fat than starches, period. As alanbarnes points out, deep-fried meats can sometimes have less fat than when raw. Sounds counter-intuitive, but it's not.