I noticed several reviewers commenting on the chemicals in lemons and their effects. I just wanted to help clarify and answer some questions. I study Biology, and therefore have a good understanding of chemistry, so you can take my word that I'm not pulling stuff out of thin air. :-)

So basically lemons work so well because they contain citric acid. Concentration of citric acid in lemons is pretty high, so if you feel like the juice is working for you but is burning, stinging, etc, you can try using grapefruits or oranges. They have a little less citric acid, and they contain more fructose (sugar), which is also good for your skin.
So citric acid helps break down (oxidizes, actually) oil, protein, carbohydrates. When used on skin, it helps break down the cell membrane. The low concentration of citric acid in lemons usually just helps the dead or dying skin cells separate from the other cells. So it speeds up the process of dead cells shedding. This in turn gives the surrounding cells feedback to reproduce quicker. Some people may notice that the lemon juice helps skin feel softer, and smoother at first, but after repeated uses causes redness, irritation, and/or damage. This is usually because the number of skin cells dying/sloughing off are more than the number that are forming.

Citric acid is in the alpha hydroxy class of acids. Most people here are familiar with alpha hydroxy acids--they are commonly used as anti-wrinkle products. Citric acid, like most alpha hydroxy acids, causes skin cells to respond to their presence by producing more collagen and less melanin. The only problem is that the chemical needs to get through the epidermis and reach the dermis (contains blood vessels). Citric acid molecules are larger and have a little more difficulty getting past the epidermis as compared to certain other acids. So don't make fun of others paying good money for skin products--they usually contain compounds that work better while reducing unpleasant side effects. The chemical structure of some compounds may be changed and tweaked to enhance their performance and decrease collateral damage. (Think citric acid without the burning, redness, damage from prolonged use)

Anyway, I think I got a little carried away here. I just meant to write few sentences, but ended up going on a diatribe (as you can already tell, I'm a Bio-nerd). But lemme just break down what I said, it might be more useful.

-Lemons are natural; just because they're natural doesn't mean they don't contain chemicals (water is a chemical, you know).
-Lemons contain lots of citric acid
-grapefruits and oranges contain less citric acid and may work well for people with very sensitive skin
-Citric acid:
-Helps dead skin slough off faster
-Helps increase collagen production: breaks down scar tissue, fills in depressed spots, makes skin more supple.
-Helps decrease melanin production: skin discoloration, freckles, sun spots, age spots, melasma fade quicker
-Citric acid can "burn" your skin. Know your skin, and make sure not to overdo.
-Use sunscreen in conjunction with lemon juice: citric acid sloughs off dead cells, leaving less of a protective barrier. The younger cells may not be mature enough to withstand environmental effects.
-Just because lemons may work well doesn't mean commercial products don't work.

Finally, I feel like I should mention that I stumbled on this product review. I feel silly for not thinking of using lemon juice for my skin earlier. I have occasion cystic acne, acne scars, and a little melasma. Citric acid should help with all of these conditions. I used some last night, and again tonight. I'll keep you posted on how it works for me!

You must try this immediately!


Skin History:


Wow. Ive spent so much money, time, and unnecessary stress over my skin, and finally the weight has been lifted off my shoulders. I finished my first (and so far only) course of Accutane two years ago, and though my acne has returned, its less severe and much more manageable. Honestly, I really don't care about active pimples, but its the scars that remain for months that drive me crazy. Nothing has vanished my scars like fresh squeezed lemon juice.


Application:


Every day, I squeeze 1/3 of a lemon and put the other 2/3 wrapped in foil in the fridge. I then squeeze all the juice into a small bowl, not really caring if the seeds fall in or not. One day I will add some cool water to the juice, and the next day I will use straight up lemon juice, alternating as to not really push the skin over the edge.Then, I take a cotton pad (or folded up toilet paper if I'm lazy), dip it in, and swipe all over my face. It usually drips onto my neck, but I let it go down anyways. You will know it is working when you feel the sting. Yes, the sting. It's pretty bad, especially the first few times you use it. My experience, however, is that I was so ecstatic with my results that I started associating the sting with pretty skin, and the pain went away. If it is really bad, do a mixture of 1/3 lemon juice with 2/3 water and work your way up. Some people wash it off after 15 minutes, I usually leave it on way longer, usually 3-5 hours or overnight. So definitely do it when you're at home and have time. Follow with a light application of your most trusted moisturizer.


Effects:


Since I started using lemon juice last month, my skin has just been...healthy, to best sum up all the amazing words I could say. Yes, I still get some (albeit much less since I started using lemon juice) pimples, but they heal much faster, don't grow as big, and don't leave as intense a red mark as they had done in the past. My previous reddish-purplish-brownish scars from weeks and months before have decreased in diameter from small rice to about kosher salt (sorry if this is random, but I put lots of thought into this analogy and it fits what I see best!). Added to this, my skin that has been unaffected by acne (skin around pimples, sides of nose, sides of forehead, and around mouth) has become healthy and even-toned. When I say even toned, I mean no redness, with a very very slight golden hue.


UPDATE


Lemon juice is still working just as well as ever. I few more benefits I noticed:

- Moisturizer goes on smoother, and I needed less moisturizer than I normally do
- Freckles around my nose haven't faded, though they have became smaller and more similar to my normal skin color
- My skin has become really really smooth. The tiny bumps that normally wouldn't bother me have receded, leaving level skin behind


Also!!!


My dermatologist was shocked when I told him that lemon juice worked so well. He said that he would have expected it to be too harsh, but I told him I'd been using it for more than 6 weeks, and he told me I could continue to use it! He also explained why exfoliation, especially chemical like lemon juice, is important for people with acne. He said that in healthy skin, skin cells are programmed to shed off one by one, reaching the top of the skin unimpeded, where it waits to be exfoliated. However, in those with acne, skin cells are programmed to die and flake around the same time, and combined with thick sebum, the pore is blocked and bam, a pimple is born. Even if sebum were thick (caused by hormone imbalance), individual skin cells could travel up without clogging the pore. The problem is when skin cells flake off at the same time. Imagine a line of people going through a door. If people go one by one, they can pass through the door. However, if two (or more) people in line are holding hands lets say, they will block the door. It is in the dna of the skin cell life cycle, he said, that explains the genetic inheritance of acne and the inheritance of healthier skin. Now, I don't know if hes truly right, but it sounded really reasonable to me, and would explain why lemon juice has been so rewarding. The lemon juice was going into my pores and breaking up the evil conglomerations of dead skin.

UPDATE # 2 September 21, 2012

Because I am back st school, I found buying lemons, cutting them here, and doing my regimen took too much time. Yeah, I know it really doesn't take that much effort, but when you're busy, sometimes you just don't really care about how you look as much (maybe that isnt a bad thing though?). So I decided to give bottled lemon juice a try. I've been using Real Lemon, and I have to say, it ain't half bad. Actually, it works better than I thought. It stings less, you can put it in the fridge so it is cooling, and its in a sanitary squirt bottle that makes application very simple. However, I noticed that it doesn't work quite as well as fresh lemon juice. If I gave the effectiveness of fresh lemon juice a 10, which I most definitely would, I would probably give bottled lemon juice between a 7 - 8. So, if you're feeling lazy, but still want some great results, or even feel if lemon juice stings too much, give bottled a try. Also, I did some research online, and bottled lemon juice legally must be at least 4.5% citric acid, whereas fresh lemons can range anywhere from 4-7. So, i think fresh lemons are naturally stronger. So now you have two great paths in which lemons can be your best friends!

UPDATE #3 October 18, 2012

I've used lemon juice every day, twice a day, for the past 3 months, and it's safe to say it is a godsend. The past month or so, I've used bottled Real Lemon and it has worked amazing


UPDATE #4 January 9, 2013

Please please please see my review for carotene supplements! They will change your life as much as...if not more...than lemon juice!

After reading the reviews on here, I decided to try lemon juice on my freckled, sunspotted face. I remove my make up with my regular cleanser (Purpose) then I squeeze lemon juice on a cotton ball and apply it all over my face--avoiding my eyebrows and hairline. It stings for a few min, that's why I took off one lippie, but its not intolerable. After it dries I give it a quick spritz of my Aquafina face spray, apply safflower oil around my eyes, then go to bed. In the morning, I exfoliate and rinse my face then use a salicylic toner and Garnier moisturizer. WOWWWW! My freckles are fading, my sunspots are fading, my skintone is more even and my pores are looking smaller, all that in THREE DAYS! The stuff I learn on MUA is amazing! If you love natural products see my review on safflower oil too--its another HG product for me. Sometimes the natural basics really are the best!! EDIT: Hubby noticed my freckles are getting lighter, and there was a cluster of them that looked like a big ol' age spot and that is nearly GONE!! WOOHOOO..thought I was gonna be stuck with that sucker for life but not since I found lemon juice!!!
EDIT: This has made my skintone so much more even..and seems to have even helped balance my oily t-zone some. Plain old lemon juice is definately HG status for me!!

5 Step Guide to Using Lemons As Skincare Products


1. Start with a room-temperature lemon. To get more juice out of mine, I put it in the microwave and zap it on HIGH for 10 seconds, then roll it around on the counter. Squeezing it gently so the skin doesn't break also helps. I've gotten nearly half as much MORE juice out this way.


2. Poke a hole in the lemon with a toothpick or short skewer, squeeze out enough to wet a cotton ball, then reinsert the toothpick and store in the fridge. It keeps longer this way, and I like my toner cold/refrigerated. Mmm, that chill is refreshing! Oh, I also like it undiluted, but you're welcome to wet your cotton ball with a bit of water for sensitive skin.


3. Apply to skin of face. Avoid eyes and neck. I rub mine over my lips to get rid of winter flakes, but your tastes may vary.


4. Don't wash off. I apply a heavy moisturizer right over the top after about five minutes. I'm talking HEAVY here. You are putting citric acid on your face.


5. Prepare for the purging and initial dry/dull skin before the results. When I first started, I woke up in the morning and found many tiny, needle-point sized pustules on my forehead, nose, and cheeks - which quickly cleared up. It also brought that "stuff" lurking inside deep, cystic acne to the surface. I had a particularly large one on my chin that was a mere hard bump before lemon juice brought it to the surface that morning. Needless to say, it shocked me. My skin also looked dull and lifeless after application, but I kept pressing on and manually exfoliating earlier in the daytime (I found lemon juice AND scrubbing at night to be far too harsh for my skin to bear it, and I didn't even have that stinging pain when I first put LJ on). My skin now glows from within, almost. Not to mention my oil production in my t-zone area is quite a bit more controlled now.



This is strictly a NIGHT routine. I wouldn't do this in the day before heading out to work. Not only does contact with sunlight bleach your skin (sometimes unevenly), but I find that sweating a lot can really make your face break out with uncontrollable itching. You could use it in the day and put sunscreen on top, but that seems to me a recipe for itchiness with all those physical/chemical barriers. I'm not brave enough to try it yet with my face, but if I ever do, I'll update.



UPDATE: It's been brought to my attention to mention that I should mention this: microwaving the lemon will change the molecular structure of the juice inside and could destroy nutrients in the process. On the same hand, heating up citric acid degrades the acid (toning down the pH more towards neutral), so adding heat might make it easier for your skin to take the acidity (undiluted). So use your best judgment on nuking your lemon. =)

I hate to rain on the lemon juice love parade, but I have to. At first, when I tried lemon juice (to fade hyperpigmentation), I was in love. I have chronically sensitive skin + this caused no problem, even used full-strength. In a week, it dramatically lightened old dark marks. But then I noticed a terrible side effect--uneven lightening. It looked like I had a light ring around the dark mark I was trying to fade. I know this uneven lightening will heal in time, but it's very aggravating to try to treat one skin condition, then wind up with another. I don't want others to go through uneven lightening problems, so thought I would pipe up. Very doubtful I would use again. If I do, it would be much less often and with just a cue tip on problem spots, AND heavily diluted.

After years of suffering from acne, assaulting my face with chemicals and being depressed seeing my sisters' and friends' glowing skin, I had almost given up on smooth glowing skin...Who knew a humble little lemon will do the trick!
I use pure lemon juice on my face every night before going to bed (15 minutes before, so it dries off when I hit the sheets) And within a week, I saw a natural glow, even skin tone, clean and smaller pores and lightning of my old scars. I just squeeze the lemon in my hand and put it all over my face like a lotion.

My regimen -(Night)
Wash face with Johnson's baby shampoo (thats the only thing that doesn't break me out), use Thayers Witch hazel with Rose, Put lemon juice before bed.
Morning - Wash face with Johnson's baby shampoo, use Thayers Alcohol free witch Hazel, dab a drop of glycerine with a drop of water on face for moisturizing and I am good to go.
I still need to wear concealer to hide acne scars, but I am amazed how little makeup I need these days after I started using lemon juice treatment in night. My skin practically glows!!!!
The only thing is - Be patient with it, give it at least 2 weeks to see results. use DAILY, no excuses. Don't use it in day time or before you go out, otherwise you will be more sensitive to sun and skin can become darker/reddish.
So far I am so happy with it, and I am glad I read about it on MUA!

Edit - I also use aspirin mask 2-3 times a week. Take 3-4 aspirin tablets, sprinkle just 2 drops of water and let it sit for couple of minutes. It becomes mushy and paste like, then add a squirt of organic honey and slather it all over my face, keep it for 30 minutes and wash with lukewarm water. Since my Lemon Juice (daily) and aspirin mask (3 times a week) routine (Its been month and a half), I have cancelled my proactive orders, threw the ZapZit tube in trash and just using these 2 treatments and it has been super!! Easy, cheap, less chemical, and clear skin...what else can I ask for! Don't wait for another day or another review, just use it, you don't have anything to loose. If it works, great, if not, at least it won't harm your skin or your wallet!

Wow! This stuff really works! I use it to get rid of those pesky post acne red marks (my skin is pale and marks easily). I'm telling you, in just one week I am seeing results! What I do is make a mixture of 1/2 lemon juice, 1/2 water and store it in the fridge. Every night, after cleansing and toning, I dip a cotton ball in my mixture and apply it to my entire face, avoiding my eyebrows (lemon juice bleaches hair!). Nothing has worked this quickly to remove these red marks, not even glycolic acid peels done weekly. It blows my mind that this has faded them so quickly, like nothing else has. Just make sure not to use this stuff full strength. About 2 years ago I tried this full strength, and it just irritated my sensitive skin. Then I read reviews about people making mixtures, so I tried that and it worked so much better for me. Doesn't really kill my acne, but that's ok since Yaz is taking care of that, for the most part. Now, instead of wearing concealer, I wear only a tinted moisturizer.

I had to add- for people that are using this (or anything else) for acne, there is only one thing that will get rid of your acne- your diet. Of course dermatologists don't tell you this, but it's true. Fo example, I know that whenever I eat lots of sugary things, like clockwork the next day I will break out. Sugar is a major cause of acne. If you eat less sugar, less white bread, less fried foods and more fruits and vegetables, it will make a big difference in your skin. My skin is so much better now that I eat healthy.

UPDATE: Just had to add, I've been using this for about a month now and my skin just keeps getting better and better! Also, the stinging goes away with time as your skin gets used to this. Good luck! And limes work just as well, I hear (though I haven't tried them; only lemons).

UPDATE 2: It's over a year later, and I still love this stuff! I am now using it full strength. I guess my skin got used to it (not in a bad way) and is now able to tolerate full strength.

I can honestly say that lemon juice works. It's a great skin brightener that also fades those spots and freckles. It really makes the skin even-toned and glow. I used it as a toner after washing my face and saw drastic results after ~30-45 days of using it twice a day. I used lemon juice concentrate. My sister noticed how 'glowy' and even toned my skin was and I have the worst skin problems (acne, hyperpigmentation) in the family. So receiving a compliment on my skin was just mind blowing.
I just moistend a cotton square, applied to my skin and left on over night. Did the same in the morning, but the juice seemed to interact with my sunscreen. Therefore, I don't recommend lemon juice for your morning beauty routine. Do mind how much you use because too much of a good thing can be bad. I was using twice a day and my skin became irritated. I've cut back, but will never give it up.
One more thing, for all of you with dark complexions, please give lemon juice a try. It will fade dark spots without making you look like Michael Jackson. It takes some time, but it WILL work.

First, I must say that I have the worlds most unfortunate complexion. I am so pale that I rarely find coverup to match my skin, I have red spots and an uneven skin tone, giant, clogged pores, and am extremely prone to breakouts, mostly around my chin. My skin was a mess. After spending a fortune on different acne products, I decided to take a more natural approach to my skin...enter, lemons. After three days of using regular, bottled lemon juice, I literally had NO breakouts, just scars. Every night after I wash my face with a gentle cleanser, I'll soak a cotton pad in lemon juice, then run some tap water over the pad to dilute it a bit, and rub it over my face like a toner. Then I let it dry on my face for about 15 minutes (and it stings like hell for the first few days, that's how you'll know it's working!) and then I put on a gentle, scent free moisturizer (spectro hydracare). Additionally, instead of using a harsh facial scrub, I now just soak a cotton pad in lemon juice, put regular sugar on it, and gently scrub my face. It is the most amazing scrub ever- leave it on for 15 minutes as a mask, and when you rinse it off, your face will be soo amazingly smooth. I've tried hundreds of dollars worth of scrubs, and nothing works like this. The scrub seems to erase my acne scars (that I've had for YEARS) right before my eyes. I can't believe I hadn't discovered this until now. My harsh red scars are now faded to what looks like freckles, my complexion is even, my pores are smaller, and I rarely have breakouts. If you make this a routine, you can have amazing skin for the lowest price possible. Go natural ladies- your skin isn't meant to be soaked in chemicals. The more chemicals you use, the more problems you'll have. Try natural remedies like lemon, honey, olive oil... it's worth it!! :)

Three nights a week I apply pure lemon juice to my face before moisturising. I have tried various vitamin c serums and glycolic acid peels in the past, but nothing has brightened my skin like plain lemon juice. After washing your face, just squeeze some lemon juice into the palm of your hand and rub it onto the face, neck and back of hands, then follow up with moisturiser. Do this three nights in a row and leave for the rest of the week. More can be too irritating.

I am in my early 40's with slightly oily skin, a few broken capillaries, but fairly normal skin. If you have dry or sensitive skin, this may not be for you. Alternatively you could try mixing the lemon juice with aloe vera gel, glycerin or rosewater to make it more gentle. Test patch first.

I use this right up to my eyes, and yes it does sting slightly, so avoid using on broken skin. This has evened my complexion, lightened a couple of age spots that nothing else had, and made my pores look smaller. I have not found that it makes my skin dry, however I have only been using it for three months, and it is winter here, may be a different story in summer.