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’ve been using Raspberry ketones drops from Natural Labs Group who sells product on amazon and I was very surprised at the great taste of this first of all so for
I have been taking this for just a few days and I noticed that I did
lose 3 pounds. What I wanted to lose was just 4 to 5 pounds. And so far
this is really working well for me. What I like the most about this is
that it inspires me to stay on a healthy diet with more protein and less
carbs!
One more thing…yesterday I added this to my morning smoothie, afternoon smoothie and it added to the taste of the smoothie and also it is a pleasant way for me to use this. And I have just 2 more pounds to go, so I am very happy with this!
Marie, happy to hear it’s helping you! Continued success.
Hi Joe,
Thank you for a great educated review of these RKs. I too am one of those who have bought some and decided to read up after. I have asthma and some intolerance issues so I was a bit concerned. I normally look all these with great skepticism and usually never partake.
But since being diagnosed with sleep apnea I am want to lose weight the easy way…where RKs come in. I know a few people who are taking them and they say it has helped them lose weight…which is why I got some from a Groupon offer (2 months supply for 800mg tablets for £22.99 inc delivery).
Your review has answered many of my questions and I agree with what you say and advise…but as I have these tablets I will try them and see what happens…
Thank again for an honest review
kash, you are very welcome and for what its worth, I hope they help. Let me know what happens.
Here is a review of weight loss supplements I wrote for my personal website. I cover the different types of supplements along with those that I feel have the most evidence. I cover other things that can help too.
I’ve been on raspberry ketones for a month and its a waste of money, I follow my diet, exercised regularly, my scales never moved, All I got out of it was a bloated stomach every day as if I was 3 months pregnant. And yes I was regular. Waste of money.
I have been taking them for a month and have lost zero pounds. They are a waste of money. A con. Do not waste your money. Want to lose weight? Eat less, eat the right foods, and exercise more. That is how you lose weight. Do not bother with RK or any other diet gimmick. If a thing looks too good to be true, it is
So I was obviously skeptical as anyone should be about any supplement. I tried the Ketones but it didnt really work for me. However I saw the Lady Soma Detox on the Dr. Oz show as well at the top of a list of best weight loss supplements so I thought I’d give it a try.
I have been taking the Lady Soma Detox for almost 3 months and I have lost 30 lbs. along with dieting (Exercise is just around the corner :). I would recommend this to anyone who is looking for a natural way to help lose weight.
FloridaMom, Really glad it helped you. I tried to look up “Lady Soma Detox Dr Oz show” but didn’t see when it was discussed on his show. I looked up the product and noticed that it contained senna which is a laxative. It also has aloe and psyllium which are also laxatives. The thing with laxatives is that they work at the large intestine (where the poop is) but they dont work at the small intestine (where we absorb calories).
Do start some type of an exercise program as it will help you keep your muscle tissue. With dieting alone, some of the weight loss is muscle. exercise helps you keep more of it.
I found your review after searching for Lisa Lyn’s credentials. She has a standing gig, promoted as a feature on my local news show WTNH in New Haven. I have no interest in her supplements nor fitness program, have no expertise in those areas either, but as someone who grew up with Type 1 diabetes, I tend to be very cynical of any supplements or protein shakes that make claims of fat burning or weight loss.
I find it very disturbing that a respected news show blatantly allows for advertising of products that have no research behind them, without acknowledging that it is advertising.
Pam, thanks for the heads up. I had no idea Lisa Lyn was doing TV segments at WTNH. Does she promote her supplements during her TV news segments?
I just started taking the rasberry ketone (only 400mg once daily) and 1 african mango supplement. I weighed 126 prior to Christmas and exercise and eat healthy regularly but was finding it hard to lose 5-10 pounds that I noticed I had put on in the last 2 years (I am a 37 year old women).
After 2 weeks of taking the pills daily and no change to my diet or exercise besides trying to increase my water intake I have lost 5 pounds! Not sure if it is the water or the supplements but I feel and look better with no negative side effects so far.
Jam, thats great! As long as it helped you, I’m a happy camper 🙂
Hey there. As far as I can tell, you’ve somewhat misquoted Dr Oz. As I recall, he said raspberry ketones “trick your body into thinking it’s younger” because of their action on adiponectin. The importance of concomitant sensible diet and exercise was stressed on the show. All results take at least eight weeks to start showing, so anyone taking a supplement for just a month won’t be able to judge the effect. It also takes a certain quantity to achieve the required effect. If you want a really good source for the latest research, go to the US National Library of Medicine http://www.ncbi.nlm.nih.gov/pubmed There you’ll find ALL the latest research from credible medical journals.
Hi Angela, All of my reviews contain links to studies at the national library of medicine. I dont remember Dr saying what you said but I will agree that he does stress eating healthy and exercise. He did indeed however call RK the “number one miracle in a bottle to burn your fat”, something Im sure he is sorry about because Ive also seen this quote also on various websites that sell RK. I just searched the National Library of Medicine and still did not see any raspberry ketone only studies showing it causes weight loss although there is some interesting test tube research. I’ll likely update my review with these new studies in the near future.
Hi Joe,
Thank you for your reply. That was also my conclusion. I think it’s a little risky to combine caffeine & bitter orange in the same supplement, due to it’s similarities to ephedra and it’s known hypertensive effect.
However the research on C. aurantium that I have seen suggests to me that it’s a lot safer than Ephedra and there have been enough positive results to make me think that there could be a small beneficial effect for weight management. There’s not enough to convince me yet but I’d like to see some more quality human trials using it alone. And raspberry ketones for that matter, if only to establish their safety for humans.
Great site, keep up the good work. If I do any trials on anything myself I’ll be sure to post here to contribute.
Will thanks for that. I am aware of various case studies of bitter orange causing problems in people. I quick check I found these:
http://www.ncbi.nlm.nih.gov/pubmed/16610576?dopt=Abstract
http://www.ncbi.nlm.nih.gov/pubmed/15830849?dopt=Abstract
http://www.ncbi.nlm.nih.gov/pubmed/11583473?dopt=Abstract
Hi Joe, I’m pleased to find you site and have enjoyed several of your well written reviews, including this one. I came to the same conclusion about RK in my own research of the evidence. I do not need to lose weight so won’t be testing it on myself.
I would be interested to know in your opinion of the METABO supplement, which contains RK amongst other ingredients. There is a study published that shows quite good results of this product in obese people. It is used in combination with exercise & diet for 8 weeks. http://www.ncbi.nlm.nih.gov/pubmed/23601452
I know some other the other ingredients have some evidence to support them and so this trial doesn’t support RK alone for weight/fat loss but I’m interested to hear your analysis.
Hi Will, I looked at the study you linked to. I think its active ingredient might be caffeine and Citrus aurantium. citrus arantium is also called “bitter orange” and is a compound that “looks” like ephedra. the best weight loss studies on ephedra if I remember, used a combination of caffeine and ephedra so in theory its possible the same thing might be going on with this combination as well. that said bitter orange is controversial because it might raise heart rate and blood pressure. I’m glad nothing like that appears to have happened in the study.
What has happened to Adrian? He hasn’t’ posted since March??
I am considering trying RK and started following his comments – I want to know what the outcome was!! A.
Angie, Im not sure he hasn’t written anything.If you do try it and it helps, let me know.
I am taking raspberry ketones by bio genetics. My Triglycerides went from 48 to 90 and my HDL went from 68 to 49. I do exercise and eat healthy. The ketones did help me lose that hard to lose last 7 lbs.
Pat, so raspberry ketones raised your triglycerides and lowered your HDL. I think you are the first so mention this side effect.
Hi I Joe, I have adrenal fatigue and was gaining weight so tried one dosage of rasberry Ketones and got not only dizziness but also my kidneys ached so no more RK. What would mean to have such a strong reaction? All medical tests say I am healthy :(.
Thanks, Mel
melanieabela, that is strange and I just dont know. I am glad your doctor said you are healthy so that’s great news. Did your doctor test your “TSH level” to see if your thyroid is working ok? That can make it hard to lose weight also.
In regards to TSH tested. All tests normal. This is the problem with the medical system. It does acknowledge cortisol levels below med standards- adrenal fatigue is only acknowledged ny naturopaths unless it gives into Addison’s disease level. Just wanted to suggest that RK are possibly dangerous for cortisol,or other kidney related imbalances. I naturally have too low blood pressure and so your column made me aware it could aggravate the problem….
Thanks, melanie
Thanks Melanie.
Asking most surgeons about metabolism is like asking a carpenter about your internet connection. Internal medicine and Endocrinology are separate residences and fellowships. I would not do major surgery except in an emergency where certain death was the only other outcome. Dr. Oz should not be making comment on weight loss or general health issues that are still not clear to the real metabolism experts.
Hi Joe,
I just now got my order of the Raspberry Ketones and also got slimquick green coffee bean to take with it. I have a lot of stomach problems that popped up after having my son. I have one ovary that bleeds into my other ovary and I also have IBS so working out is slim for me because of pain.
My doctor put me on the depo shot to slow the bleeding in my ovary down and i went from 135 pounds to 155 pounds on it so I stopped taking it and i decided to try these diet pills along with some P90X workouts. SO i hoping that the 2 pills together with what workouts i can do on the P90X helps me get the weight back off.
I will be starting it either this evening or tomorrow and I will keep updates on how it acts with me.
Also with the payment problems everyone has had I used my paypal account to order mine so hopefully i dont have bank problems with this like everyone else has.
Sarah, I hope this helps you. Id suggest you start the first week with only one of those supplements, just to see how you respond and cut down on any side effects that might pop up. if you did this, you would be able identify what might cause problems if you had any. Good luck Sarah and smart idea using Paypal 🙂
Hi, Ive just started raspberry ketone two days ago. I was so skeptical, but honestly it does really help. I wanted something for energy and to lose weight, and it helps me not eat so much. I only take one in the afternoon/morning after i eat a meal and water, and it makes me feel good. Im surprised, and no nauseousness. But i think you have to believe in yourself, if you believe it works, it will work. But its a great pill, Ive found that its helping the stomach area, and im trying to lose a lot of weight.
I have been taking RK for around two weeks now and keep having very hot flushes, like every 20 minutes or so and keep needing to go for a wee – has anyone else experienced this. I have also had a few more headaches and feel tired as now cannot sleep at night!!
Melissa, I’d say stop taking it and see if your symptoms go away. that will tell you if RK is the cause of them. You should have your answer in a few days.
I found RK worked better the worst I ate. Lost 3kgs on fraser island in one week. Ate nothing but meat and potatoes and drank copius amounts of alcohol. Crazy
Luke, are you sure all that alcohol didn’t blur your vision as you were looking at the scale 😉
Nah mate, seeing how it was two days after I came back. Smartass
I received a bottle of Puritan’s Pride Raspberry Ketones free in a monthly fitness kit that I receive. I was hesitant to try them because supplements can be so tricky and have so many side effects. I’ve decided to go ahead and give it a shot, while monitoring my blood pressure which is usually on the low end of normal.
Thank you for the research you’ve done. I’ve got low expectations for what may happen but figure it’s safe enough to try for now. I’m only on my second day and raspberry flavored burps is all I’ve experienced (not as delightful as you’d think).
Lea, thanks for the feedback and I hope RK works for you. I can live with a few raspberry burbs but I’m sure its a bit annoying at times 😉
I purchased a bottle of this supplement and was not told about possible side effects. In fact I was told it was stimulant free and all natural. Boy was I wrong!!! I took one dose and experienced issues with increased heart rate, profuse sweating, and in general felt like I was short of breath. I had to take a moment to sit down because it made me feel insanely weird!!
I’ll never take it again after reading your article I’m fully aware now that it may be a stimulant and not ok for individuals who are sensitive to those sort of things. Be careful! I’ll stick to my multivitamin and amino acid supplements.