Update 9/14/19. What are raspberry ketones and do they work? Well, if you watch the Dr. Oz Show, you may have heard Dr. Oz call raspberry ketones “The #1 miracle in a bottle to burn your fat.” Since he made that bold statement, I've heard that raspberry ketone supplements are sold so fast that vitamin stores can't keep them on the shelves! So, what I'd like to do is review the raspberry ketone research — minus the hype that you have already heard about. Only in this way can you make an informed decision about whether raspberry ketone is right for you. Other names for this supplement include red raspberry ketone, and European red raspberry, as well as the more scientific names Rubus idaeus, Rubus strigosus and Framboise Rouge. I'm telling you these other names because if you just searched for “raspberry ketone” you may not find all of the information available. For this review, I'm pretty much going to stick to just calling it raspberry ketone.
What Are Raspberry Ketones?
Red raspberry ketones are one of many compounds in raspberries and are what gives raspberries their unique smell. Like all things that come from fruits and vegetables, raspberries contain a lot of substances that are healthy —including anthocyanins, vitamin C and beta carotene. As such, raspberry ketones are also antioxidants.
Raspberry ketones also “look” similar to synephrine and capsicum — two ingredients that have been used in many weight loss supplements over the years such as the fat burner promoted by Jillian Michaels. This similarity is likely why scientists considered raspberry ketones as a weight loss agent itself.
Weight loss supplements that contain raspberry ketones include QuickTrim — the Kim Kardashian supplement —and Apidexin. See my reviews on those products for more information.
Ketone trivia. The name ketone is a chemistry term. That's not important. I just thought people might like to know where the word came from. On some websites they spell ketone as “keytone” but this is an incorrect spelling of the word. Again, not important.
Tip. Keep in mind as you read this review that raspberry ketones are not the same thing as ketones that are made when people go on low-carb diets or in people who are diabetic. Those ketones are not the same as raspberry ketones.
Raspberry Ketones And Weight Loss
When Dr. Oz asked his fitness expert, Lisa Lynn (more about her below) on TV, how she found out about the weight loss properties of raspberry ketones, Lisa said “Research research research.” So, I looked up the research on raspberry ketones and this is what I discovered.
In a study published in 2005, titled the Anti Obesity Action of Raspberry Ketone, the supplement was given to mice that were fed a high-fat diet for several weeks. Mice were split into different groups, each getting the same calories but getting different amounts of raspberry ketones (either 0.5%, 1% or 2%).
The diets were about 40% fat in each group. Researchers noted that raspberry ketones — that made up between 1% and 2% of total calories — caused a reduction in body weight and fat buildup in the livers of mice after 10 weeks of use, compared to mice that only were fed a high-fat diet.
Norepinephrine (also called noradrenaline ) is a chemical made in the adrenal glands that act as a neurotransmitter and does many things, one of which includes helping to burn fat. This study also incubated isolated mouse fat cells in norepinephrine along with raspberry ketones to see what would happen.
The researchers observed that the combination of raspberry ketones and norepinephrine caused more fat to leave the fat cells than norepinephrine alone.
This is why Dr. Oz said raspberry ketones cause fat cells to shrink.
I'm telling you this because various websites claim that raspberry ketones increase levels of norepinephrine. However, this study did not show that.
Rather, the researches only showed that raspberry ketones appeared to improve the fat-burning ability of norepinephrine.
This is actually a good thing because too much norepinephrine can be bad. For example norepinephrine can raise blood pressure.
Oddly, this study noted that while a 1% intake of raspberry ketones tended to raise triglyceride levels in the mice, eating it at a concentration of 5% of total calories tended to reduce triglycerides.
These researchers also quoted previous studies noting that raspberry ketones raised metabolic rates—in rats. That's interesting, but where's the proof that raspberry ketones raise metabolism in people?
Bottom Line: This was just a mouse study —and a small study at that! Each group only had 6 mice.
Also, if we really want to be technical, all the mice were male. What about female mice? Would raspberry ketones have the same weight loss effects in female mice —or more importantly —women?
In another study, published in 2010, researchers found that red raspberry ketones inhibited weight gain and improved fat burning in mice that were fed a high-fat diet. Researchers also noted that raspberry ketones increase levels of adiponectin, a hormone made in fat cells.
The Wikipedia page on adiponectin goes into more detail, discussing how the hormone does a variety of things including improving the sensitivity of insulin— (good for diabetics).
Dr. Oz said that Adiponectin was the “hormone that tricks the body into thinking it's thin.”When we put on weight, we reduce the ability of the adiponectin hormone to work.”
Sounds good, but red raspberries have only been shown to reduce adiponectin in mice. What about people? Have raspberry ketone supplements been proven to help people lose weight by raising adiponectin levels? Nope. Not yet.
Tip. There is more evidence that exercise raises adiponectin levels than for raspberry ketones —and exercise has been shown to work in people!
One study from 2013 appeared to show that a supplement – containing raspberry ketones – helped weight loss. But there were several ingredients in that supplement. Also, of the 70 people who originally signed up, only 45 people made it to the end. That's a big drop amount.
There is a study published in 2017 that noted, that raspberry ketones might reduce food intake in mice who were fed a high-fat diet. Again, this is a mouse study.
So, what's the evidence for raspberry ketones and weight loss? It looks like some mouse studies. What about people?
Are Raspberry Ketones Better With Capsaicin?
Capsaicin is found in chili peppers and synephrine is an extract from oranges. Both have been used in weight loss products in the past. Because raspberry ketones “look” like both capsicum and synephrine, I predict that you will see weight loss products that have all three of these ingredients.
But, would they all work better together? I don't know because there is no proof either way. Because of that, I recommend you save your money on weight loss pills that combine (“stack”) capsaicin, synephrine, and raspberry ketones.
Synephrine, in particular, is not without problems. It can raise heart rate and blood pressure which can make it dangerous for a lot of people.
Who Is Lisa Lynn?
Dr. Oz called Lisa Lynn a “fitness expert” on his TV show when he did a segment on this supplement— but who is she? I checked into her background and found her website (LynFit.com) that notes that Lisa Lynn was the personal trainer of Martha Stewart.
Her website does indicate that Lisa holds multiple personal training certifications.
All this is fine but on her website, we see Lisa Lynn also has her own line of supplements (called “Lyn Fit”) She even has a 
raspberry ketone supplement on her website.
In a previous segment of the Dr. Oz show, Lisa Lynn also extolled the virtues of the metabolism booster/weight loss supplement, Coleus Forskohlii. Lisa has this supplement on her website also.
See the review on Coleus Forskohlii for more information.
Look, I'm sure she's a nice person and a great personal trainer —and I am all for capitalism – but where is all the raspberry ketone research? As far as I see, it's just some mouse studies.
How Much Raspberry Ketones Do You Need?
If raspberry ketones help people lose weight, how much works? Nobody knows because there are no human studies of raspberry ketones and weight loss. If we believe the mouse studies (which I don't), it appears that a concentration of 1% of total calorie intake might help weight loss. If that is correct, then the number of raspberry ketones needed would be different for different calorie intakes.
For example, a person who consumes 1800 calories per day would need less than a person who eats 2000 calories per day.
When asked “how much works” on the Dr. Oz Show, Lisa Lynn said to take 100 mg at breakfast— and if that didn't help, to go to 200 mg. Where did she get these numbers from? She doesn't tell us.
I guessing that this might be the human dose, extrapolated from what researchers gave the lab mice? But, I see no good proof that 100-200 mg of raspberry ketones per day helps people lose weight. It might—but I just don't know.
In this toxicology report on raspberry ketones, the authors mention a dosage of 100-1400 mg per day is often mentioned on the internet. That is a pretty big range, which again, says to me, nobody has any idea.
Raspberry Ketones And Appetite
Various websites make the claim that supplements can reduce appetite. But I see no proof of this. Even the mouse studies, do not state that raspberry ketone supplements suppress appetite.
Anti-Aging Effects Of Raspberry Ketones
Can raspberry ketone supplements slow down the aging process? Do they reduce wrinkles? Well, red raspberry ketones do have some antioxidant effects but it's a long shot to go from that to say that they are “anti-aging.”
Raspberry ketones may be found in some cosmetics because they seem to have a skin whitening effect —at least in skins of mice. That's fine, but I recommend you save your money on raspberry ketone anti-aging supplements. They are not an “anti-aging superfood.”
For those who really want a “superfood,” eat raspberries! Here's why: antioxidants work best in small amounts and when they are eaten in combination with the other ingredients in food. Because of this fact, raspberries are better than raspberry ketone supplements when it comes to being healthy.
Raspberry Ketone Side Effects
In healthy people, raspberry ketones are probably safe. That said, those who are not healthy or take medications should speak to their doctor/pharmacist first. Here are a few things to consider when taking this supplement. This list is not complete.
- Start with less than recommended for the first week
- Pregnant or nursing women should also speak to their doctor
- Stop taking the product at least 2 weeks before having surgery
There are only trace amounts of raspberry ketones in raspberries so they are no the same thing as supplements. This toxicology report states that there is only 4.3 mg per 2.2 pounds of raspberries. Just because raspberries are safe does not mean concentrated supplements of raspberry ketones are also safe.
One of the mouse studies summarized above noted that raspberry ketones raised triglyceride levels. Does this mean they also raise triglycerides and cholesterol levels in people?
Since raspberry ketones appear to have some chemical similarity to synephrine, be careful if you have high blood pressure or heart conditions. Synephrine might raise blood pressure and heart rate.
A report from Denmark publishedhas raised some concerns that the supplement may have toxic potential but there is little human evidence for this.
Some have speculated that these supplements may be inappropriate for those with cancers that are sensitive to estrogen levels. This is based on a concern that raspberry ketones may have estrogen-like properties. Cancers that might be affected by this include breast cancer, fibroids of the uterus, endometrium cancer, and uterine cancer.
In the book Herbs of Choice raspberry leaf is said to help with pregnancy issues such as morning sickness and labor pains. The book also notes (p. 140) that raspberry appears to promote contraction of the uterus. That would not be good for pregnant women. Would the same be true for raspberry ketone supplements? I don't know.
Do these supplements raise blood pressure? I do not know, but if the leaf of raspberries cause the muscles of the uterus to contract, what effect would they have on the muscles of the blood vessels? Would they also contract (and raise blood pressure) or would they relax (and decrease blood pressure)? I don't know.
Remember, some raspberry ketone supplements may contain more than just raspberry ketones. Always check the labels to see what other ingredients a supplement may contain.
See What Weight Loss Supplements Work for a list of things I feel have evidence
Do Raspberry Ketones Work?
The research on raspberry ketones for weight loss is in its infancy. As such, I just don't know if this supplement helps people lose weight or not. The majority of research is a lab rat and lab mice research. Raspberry ketones may benefit in mice but what about humans? I'd like to see a real-life study of of 100 people followed for at least 6 months under real-life (not laboratory) conditions to judge its weight loss power.
If you are still thinking about trying raspberry ketones to help you lose weight, I suggest you go to your doctor and get your blood work done first —cholesterol, blood pressure, weight, liver enzymes, the works—and then get it done again in a couple of months to see if anything has changed.
There are a LOT of websites that sell raspberry ketones. If you read the comments here, you'll see how some people talk about how their credit card was charged more than once after they purchased a product. Know who you deal with. Make sure the raspberry ketone websites you deal with have a contact phone number with customer support people who can help you have questions.
If they are going to work, keep in mind that it might take 6 months before raspberry ketones help you lose weight. Oh, and if you watched the Dr. Oz show, you also heard that you still have to exercise and watch what you eat too. So, you have to eat right and exercise as well as take raspberry ketones. That sounds less like “a miracle in a bottle to burn fat” and more like common sense.
I just adore reading comments..I got a great laugh and I think, I just think I might have lost some weight..i do feel a little cramp ..great article by the way. I wanted to do some research on my own but after reading this i dont want risk taking raspberry ketone and gain anymore weight then already have.
I secretly like being a little heavier than most..so ill just keep taking the steps at work, and eating right when I remember, I might go to zumba if my work day isn’t stressful and ill make my hubby knows bringing cookies into the house is a sin.
I might lose a pound or two..but I’ll be ok…we r all predestined anyways when its your time to go its your time to go …healthy or not
Thank you for this article. Well written and thorough. I think the problem with us and our society is that we have forgotten how good real food tastes. Honest ingredients, no preservatives and least processed. Instead we are poisoning our bodies with all the junk that is so easily available and than try to find a quick-fix to feel better.
Articles like this and Dinnerella are promoting us to come back to common sense and real food. You’re so worth it! Speaking of which… ‘an apple sliced and mixed with a handful of raspberries and sprinkled with flaxseed’, anyone?
Well i went to the vitamin shop and a worker told me about raspberry ketones with green tea extract so i bought them to try them out. I will post my results in a week. For now this is the first day. And i have to admit i can feel my body warm up and i think it might actually work.
Good luck everyone
I take 250 mg raspberry along with 1000 mg white kidney bean extract, once or twice a day depending on my carb load. In a matter of 8 days I dropped 2.5 lbs. The most noticeable was the reduction of body fat and appetite. I haven’t suffered any side effects. The body fat seems to continue diminishing. I still sleep fine. This is the first combination that has worked for me. I don’t take any prescription meds, so this combination has to be the effective duo for me.
i have been taking the raspberry ketones with dr. oz pictured on the front for nearly a month now and have lost quite a bit of weight, probably at least a dress size including healthy eating and purchase of a treadmill! i think they work and iv had no side effects either, i think every ones body works differently hence lots of mixed comments, i will continue to take the rk
Chloe, what is the name of the raspberry ketones that has the picture of Dr Oz on the bottle? I did a search online and didn’t see any. I really dont think Dr Oz sells any supplements that bear his image or name (I dont think he sells any supplements at all). I’d bet “his people” would like to know that his name/likeness were used to sell this supplement.
Thanks very much for a well written article. Just received the RK supplements in the mail for the wife and I (wish now that I hadn’t ordered 90 day supply). Bought them through groupon, so at least saved a little. We will try them, but thanks to your great article and your readers responses, will be ready to jump off at the first sign of problems.
Joe what do you know about green drinks as a supplement? I had a green drink every morning for about a year and felt great and kept weight off with some exercise and proper nutrition.
Then a few months ago I had lots of stress and went on a sugar/carb binge. I decided a couple weeks ago to start back on the green drink. I add it to 3 oz of yoplait light and 3 oz of milk. I feel much better, sleep much better and have more energy than when I dont drink it, and have lost about 4-5 pounds in the two weeks. Of course I have cut back on sweets, but not completely.
I wish everyone the best in whatever they try, but we all have to realize there is no miracle cure, it takes a little sweat and determination along the way.
Hi Doug, I have no problem with “green drinks” overall and if you felt better when you drank one a day, I think thats fine. Most green drinks if I understand it contain dried vegetables and maybe some fruits as well as other things. Again, if it worked for you then I’m all for you going back to them.
Thank you for ani interesting article. I came to know this product through one of my coworkers. She told me she is trying this product after Dr. Oz’s show. I told her that she should do more research on it. Your article is a perfect one that I can show it to my coworker. I always tell people to loose weight by exercise and reduce carbohydrate intake.
Raspberry ketones did not work for me. Bought a 3 month supply–buy 2 get one free–endorsed with Dr. Oz’s picture. I should send an email to him also.
Mary, wow was Dr Oz’s picture on the bottle of raspberry ketones?
I moved house while on raspberry ketone. I absolutely gained weight, about 3 pounds a week, even though I was exercising and doing much more work than normal. I stopped when I had serious and sudden constipation. I have a very healthy diet with lots of fiber, this was the only change. I drink heaps of water.
I saw one other post where someone gained weight, and I’d like to know what is different about our systems. I know that ADHD kids respond differently to amphetamines. I’m not ADHD, so I am wondering. I do have Candida and I am lactose intolerant.
Nancy, here is my guess at what happened. You said you were exercising more than normal. Sometimes when people start an exercise program, they gain weight in a week or so. This is a normal adaptation and its healthy. the weight gain is due to storage of carbohydrates (its called glycogen) and water. Every 1 gram of carbs holds about 3 grams of water. So, if you gained 1 lb of carbs, you also gained about 3 lbs of water. The result = 4 pounds of weight gain. Most people wont gain this much. I just used this example to keep the math simple.
I think this might be what happened with you. I cant be sure, but I think it at least played a role. Remember, this is a healthy weight gain. you need the carbs and water if your going to keep exercising. the body is just trying to help you out.
We all have different responses to different supplements…I find that the RK do work for me..I have taken them for about a week and I lost 5 lbs. It’s not much, but it’s something. I didn’t hear it on Dr. Oz as I don’t really watch tv. It was recommended to me by a friend.
Hey Liz, glad it has helped you. I would point out that I think the 5 pounds that you lost in a week, were likely mostly water weight (due to loss of glycogen). There was some fat loss yes, but most of it was water. thats not really a bad thing but I just wanted to mention that. Here’s a little more on this http://www.joe-cannon.com/low-carb-diets-how-they-work/
Don’t waste your money on Raspberry Ketone, there is absolutely no clinical evidence of it having a weight loss effect on humans.
Check out this article: http://inews1.net/raspberry-ketone
I just started taking a 100mg Raspberry Ketones today. And I took 1 pill so far. About 2 hours later–excuse my grossness– I got really bad diarrhea and gas that smelt horrific. Now sometimes that is natural for me. I get tummy troubles when starting new medicines a lot. So I’m not sure how it’s gonna work out. But I’m going to continue them for a while and see what happens.
As far as Green Coffee Bean Extract goes. I started taking them about 3 weeks ago. I wanted to purchase the “Pure Health” brand. But my local stores have been sold out. So I purchase one called “Thin Tab” which also has Green Tea in it. I walk a mile here and there. But I didn’t really increase exercise. And I still ate junk food. (cookies, chips, chocolate.)
After 3 weeks and 2 bottles of it, I lost 10 pounds. My doctor confirmed it. I was so excited. So I’ve decided to continue that. Saw my store had the “Pure Health” brand in today. So I grabbed me a bottle. Since it’s pure, it might work better. I would like to see which brand would be best. Hope it continues to knock off the pounds.
Being an employee at a Gnc store I see people who are duped into purchasing an ingredient recommended by the infamous Dr. Oz. At my store in particular we educate and allow the customer to make a decision based on our knowledge. We always tell them that he recommends ingredients that work well in conjunction with other products. The problem with most viewers is that they want a good quick and cheap fix which is nearly impossible.
I always doubt the weight-loss “miracle pills” (and the “10 minute a day exercise plans”) – especially since most of them do seem to say that the people in the study were on a better diet and exercising. Duh! “It’s amazing . . . I lost weight by taking this little pill . . .and eating healthy and working my butt off. The pill works!” I don’t think so. 🙂
Thanks Joe – for all you do to dig into these things for us! I know that your opinions might not be popular with mainstream and those that want to make a ton of money off their products . . . but I’d rather have the truth and not a fairy tale fed to me!
Lori, thanks I appreciate that – and BTW, that’s a nice website you have. You’re a very good writer too! 🙂
I just spoke to a sales rep from Pure Health, touted by Dr. Oz, & was actually researching the Green Coffee Bean miracle craze lately endorsed by Dr. Oz, & she wanted to sell me that plus raspberry ketones. I almost fell for it but decided to do further research & ended up here…& really glad I did! Great info & interesting mixed reviews, but rk is out for me because I already have a sensitive stomach & had endometriosis removed years ago but was severe so doc wanted me to avoid hormones because of risk of cancer.
I wish you had more info on green coffee beans, but I’m really skeptical now. Seems like it inhibits bad carb absorption, & I don’t eat much of that at all. Problem is, I lost 50 lbs over a few years with weight watchers, took it nice & slow & changed my eating habits. I loved it! Then I got stomach problems & I really couldn’t eat! Nauseous or throwing up did me in. That was a first for me but couldn’t find the source.
Anyway, I lost another 20 lbs, too much but I secretly loved it. Then ruptured a vein in my leg for no particular reason other than maybe because I was throwing up so violently, & didn’t know I was loosing lots of blood internally until I couldn’t stand or walk anymore. Trip to the ER & many tests & 3 weeks later finally came home with a walker to face 2 months of in home nursing then 6 months of PT.
to finish my saga, I got my appetite back but continued to eat well & weight watchers portions, but started to gain weight very rapidly! Five lbs a month! Been really watching what I eat & I keep on gaining! Now up 60 lbs! Don’t know what to do. I think my metabolism died on me.
I’m still regaining my strength & admittedly depressed & sleep a lot & sedentary, but started back with my yoga & Pilates daily for past month & still no help. I don’t know what to do now. Down to 1000-1200 calories daily, 5’6″ & 62 years old. What to do? Doc says he doesn’t know why & cardio cardio cardio. I have serious limitations with that. Does anybody have any suggestions?
Kay, wow sorry to hear about your problems!. have you tried exercise in the pool? water exercise might let you work around your limitations. Also, when you gained 5 pounds in a month, I think most of that was water weight, not fat. its common to gain water weight fast after gonig off of a diet or eating less calories. Ive written about this on my other website heres the link http://www.joe-cannon.com/low-carb-diets-how-they-work/
Have you ever consulted a registered dietitian? they may be able to offer advice. you can find an RD in your area at this website : EatRight.org
Thank you for your honesty and your researches, it is very helpful
Tried a few supplements over the years (without success), maxed out at 319lb – Now weigh 216lb achieved through reducing saturated fat intake and moderate exercise. However, greatest weight loss achieved while eating (of all things) 4-6OZ of raspberries + cherries for breakfast. Could be completely coincidental but would recommend the natural fruit against any extract any day.
Thank you for your extensive research , it has saved me money AND time .
I began taking the RK on August 31, 2012. The first day seemed fine but the second day I had a little tummy trouble which I passed off as weather related. By the third day I began to feel sick and I noticed I was feeling hot and sweaty and my knees ached.
Yesterday, about an hour after taking a dose I suddenly felt as if I had just run a marathon. I had no energy and could not stand for long let alone walk across the room My joints were killing me and between becoming suddenly hot and then sick to my stomach I feared I had had a heart attack.
I made my way to the bedroom and collapsed for over an hour.
Today I am feeling better but I will never take another one of those pills.
Excellent article and great comments. The one that resonated the most was the 25 year old with O blood type. Obviously, just like most diets, they work for some people and not for others. My plan is to buy some, and have the kinesioligist muscle test and see if my body wants it or not. If you don’t believe in muscle testing (I sure didn’t before it helped me), maybe trying it is reasonable if the money you spend is not a sacrifice and you are on the lookout for side effects and prepared to stop.