Have you heard of the anti-aging supplement Protandim? Maybe you saw a Youtube video of when Protandim was featured on ABC's PrimeTime news show a few years ago? Either way, Protandim, called an “Nrf2 activator” is said to be the “only supplement clinically proven to reduce oxidative stress in humans by an average of 40 percent in 30 days.” That’s fancy talk that basically means that Protandim is a type of antioxidant supplement. Unlike other products however, Protandim is said to work by helping the body increase its own natural antioxidant enzymes. Sounds good, but does Protandim work or is it scam? These are some of the questions I want to address in this Protandim review. The good thing about Protandim is that there are actual, published peer reviewed research studies on this product. I will use that research in this review and try to put it in context. My hope is that by the end of this, you'll have a better idea whether Protandim is right for you. Also see Elysium Basis Review.
What Is Protandim?
Protandim might sound like a drug but it's really a dietary supplement that is said to combat free radical damage (oxidative stress) by stimulating the production of the body's own natural antioxidant enzymes such as catalase, superoxide dismutase (SOD) and glutathione. So, instead of taking individual antioxidant supplements (like vitamins C, E, etc.) in the hopes that they will battle free radicals and combat aging and disease, Protandim is supposed to ramp up your own naturally occurring free radical defenses.
The product website (Protandim.com) says that Protandim is “clinically proven to reduce oxidative stress to levels of that of a 20-year-old.” Oxidative stress refers to the stress (cellular damage) caused by free radicals. Protandim is made in the US but is not organic or kosher.
What Does The Name Mean?
While it's only a hunch, I'm guessing the name “Protandim” was chosen because the ingredients in the product are supposed to “pro-actively” work “in-tandim” to help defend us against aging and disease.
Remember, Protandim is touted to work differently than other supplements. Instead of supplying us with something we are lacking (like vitamin C, for example), Protaindim is supposed to work by helping the body increase production of it's own natural compounds (like superoxide dismutase), which in turn, helps improve health.
That's my theory anyway.
Who Makes Protandim?
Protandim is a product of a company called LifeVantage Corporation. LifeVantage is actually a publicly-traded stock on the NASDAQ. It's stock symbol is LFVN.
The company is located at 9785 S. Monroe Street, Suite 300 Sandy, UT 84070. If you google this address you will see a building that says “LifeVantage at the top. That is good. It tells us the company has a physical location.
To contact LifeVantage by phone, the website lists this number: 866-460-7241.
The Better Business Bureau gave LifeVantage a rating of “A-“ at the time this review was written. Because ratings can change from time to time, see the BBB file for updates and more information.
According to the product's website, there are 5 ingredients in each caplet of Protandim:
|Amount Per Serving (1 caplet)||Percent Daily Value|
|Calcium (as dicalcum phosphate & calcium carbonate) 77 mg||8% DV|
|Proprietary Blend Consisting of the following||675 mg|
|Milk thistle extract (Silybum marianum) seed.|
|Bacopa extract (Bacopa monnieri) whole herb|
|Ashwagandha extract (Withania somnifera) root|
|Green tea extract (Camellia sinensis) leaf|
|Turmeric extract (Curcuma longa) rhizome|
Notice in the table above that they tell us the source of each ingredient:
- The milk thistle extract is derived from the seeds of the plant
- The bacopa extract is derived from the whole plant
- The ashwagandha extract is derived from the root of the plant
- The green tea extract comes from the leaves of the plant
- The turmeric extract is derived from the underground stems (rhizome) of the plant
This might not mean much to most people. The information is provided for those looking for more a more in-depth breakdown of the ingredients.
While, label does not tell us how much of each of the ingredients adds up to 675 mg in the proprietary blend, the Protandim US Patent. The patent informs us that the proprietary blend is composed these amounts:
- Milk thistle extract 225 mg containing 70%-80% silymarin
- Bacopa extract 150 mg containing 20% bacosides or greater
- Ashwagandha root powder 150 mg
- Green tea extract 75 mg containing 98% polyphenols (and 45% EGCG)
- Turmeric extract 75 mg containing 95% curcumin
The product label also tells that that the supplement has these other ingredients”
- Microcrystalline Cellulose
- Croscarmellose Sodium Silica
- Modified Cellulose
- Stearic Acid
- Magnesium Stearate
- Medium Chain Triglycerides
These additional ingredients likely play no role in the effects or benefits of the product. They likely are what make up the caplets and/or help with the delivery of the product into the body.
The active ingredients in Protandim have been covered previously in other reviews. For example, for more information on:
- Milk thistle, see the review of the testosterone booster, Syntheroid
- Ashwagandha, see the review of Mdrive, a supplement for men over 40
- Bacopa, see the review of the weight loss supplement 1Db Goddess
- Green tea, see the review of Mega T Green Tea
- Tumeric, see the review of the joint pain supplement Tissue Rejuvenator
As such, I won't reinvent the wheel, by covering those ingredients again. Instead, let's look at the actual scientific research on Protandim itself because I feel this will help people get a better perspective of the product.
Before we start, I want to commend the company for sponsoring much of the research below. Its rare to find a product with so many clinical studies.
Protandim is different from a lot of supplements because there really is published, peer reviewed research on the product. Below is a summary of the Protandim research I uncovered with links to these studies for those who want to see them for themselves.
Because scientific studies can be, wordy and difficult to understand for most people, I will summarize the study and put the research in proper context to make them easier to understand.
2016 Protandim Research
This study was performed to see if taking Protandim (675 mg/day) for 90 day would improve 5K running performance and reduce TBARS. The study involved 38 runners who were randomly given either Protandim or a placebo. After 90 days, those taking Protandim (1x/day) showed no improvement in running performance compared to those taking the placebo.
In addition, Protandim did not reduce TBARS or alter levels of antioxidant enzymes superoxide dismutase (SOD) or glutathione peroxidase (GPX) during resting periods. The researchers report however that in those over age 35, Protandim improved SOD twice as much as those taking the placebo.
A 2016 study titled Longer lifespan in male mice treated with a weakly estrogenic agonist, an antioxidant, an α-glucosidase inhibitor or a Nrf2-inducer, sought to determine what effect various compounds had on extending the life of mice. Protandim was one of the compounds tested.
The other compounds tested in the study were fish oil, ursodeoxycholic acid (a bile acid, used to dissolve gall stones) and the diabetes drug, metformin. Different mice received the different compounds for their lifespan.
Beginning at 10 months of age, mice recievdd protandim at a dosage of 600 parts per million (ppm) in their food. This amount was chosen because it was similar to what people use when they use Protandim.
When the mice were 17 months old, the dosage was increased to 1200 ppm because this was thought to be better.
At the end of the study, researchers noted that male mice getting Protandim had a 7% increase in average lifespan. There was no life span increase in the female mice getting Protandim. The researchers only speculated on why female mice so no improvements. The researchers also point out that while average lifespan was increased, maximum lifespan did not increase.
2013 Protandim Research
In 2013 a study titled Nrf2 activation: a potential strategy for the prevention of acute mountain sickness was published in the journal, Free Radical Biology and Medicine. This was basically a test tube study.
On January 2 2013, LifeVantage announced a new peer reviewed study on Protandim. The name of the study is Upregulation of phase II enzymes through phytochemical activation of Nrf2 protects cardiomyocytes against oxidant stress and it appears in the Nov 30th issue of the journal, Free Radical Biology and Medicine. In a nutshell, this study noted that treatment of mouse heart cells with Protandim increased production of an antioxidant/anti-inflammatory enzyme called Heme oxygenase 1 (HO-1) as well as Nrf2.
This was not a human study but rather, basically a test tube study using isolated mouse heart cells.
It appears that this study is actually derived from the Master's Thesis in 2010. The title of the MS Thesis is “UPREGULATION OF HEME OXYGENASE-1 AND ACTIVATION OF NRF2 BY THE PHYTOCHEMICALS IN PROTANDIM .” It is not unusual for a quality MS thesis or other graduate work to go through the peer review process and be published.
2012 Protandim Research
Study Name:Antioxidants for the Treatment of Patients with Severe Angioproliferative Pulmonary Hypertension? Published in the journal, Antioxidants in Redox Signaling.
Summary: This is a rat study. Protandim increased antioxidant enzymes in rats, protecting the hearts from damage.
Study Name:Phytochemical activation of Nrf2 protects human coronary artery endothelial cells against an oxidative challenge published in the journal, Oxidative Medicine and Cellular Longevity.
Summary: This is a test tube study. Human coronary (heart) artery cells were treated with Protandim. The concentration of Protandim was 20 micrograms per milliliter or placebo (ethanol). All cells were then treated with hydrogen peroxide (H2O2) to induce free radical damage. Cells treated with Protandim showed less cell death than those getting the placebo.
Study Name:Protandim does not influence alveolar epithelial permeability or intrapulmonary oxidative stress in human subjects with alcohol use disorders. Published in the American Journal of Physiology. Lung Cellular and Molecular Physiology.
Summary: This study showed that Protandim did not work. This was a strange study. Researchers looked at 30 people who abused alcohol. The researchers stuck tubes down the throats of the subjects to take fluid samples from their lungs. They randomly gave the people 1350 mg of Protandim per day or a placebo, for a week. They tested for various things to see if Protandim helped the people. It didn’t.
Personally, I don't know how relevant this study is to whether Protandim works or not. I mentioned it because it was a human study. For a much more in-depth review of this study—written by a doctor—see the Protandim review posted on ScienceBasedMedicine.org.
2011 Protandim Research
Study Name:Oxidative stress in health and disease: the therapeutic potential of Nrf2 activation. Published in the journal, Molecular Aspects of Medicine.
Summary: This is a test tube study. The summary of the study I linked to says that Protandim altered cellular pathways involved in not only antioxidant enzyme production but also those involved in colon cancer, cardiovascular disease (heart disease) and Alzheimer's disease. But, humans are more complicated than isolated cell cultures. This study doesn’t prove Protandim reduces the risk of any of these diseases.
Study Name:The role of manganese superoxide dismutase in skin cancer. Published the journal, Enzyme Research.
Summary: This is a mouse study. In the study, researchers reported that Protandim reduced tumor growth in mice. But, how much Protandim did the mice get? If that information is in the study, I could not find it. For the most part, this appears to be a review of previous research relating free radical damage to the development of skin cancer. The actual study isn't even discussed until you have read half of the paper—and then it's only a vague description of the research.
Study Name:Protandim attenuates intimal hyperplasia in human saphenous veins cultured ex vivo via a catalase-dependent pathway. Published in the journal Free Radical Biology and Medicine.
Summary. This is a test tube study. In this investigation, Protandim was cultured with the saphenous vein (a vein in the leg that is used in heart bypass grafts). Researchers noted that Protandim reduced the thickening of vein cells. This, in turn, helps the veins last longer, which is good for those who have bypass grafts.
When I say “test tube study” I'm making a general reference to any study that's not conducted on lab animals or humans and involves cells that are isolated from the body from which they were taken. Test tube studies are valuable, but they may not represent what goes on in human or animal bodies.
2010 Protandim Research
Study Name: The Dietary Supplement Protandim Decreases Plasma Osteopontin and Improves Markers of Oxidative Stress in Muscular Dystrophy Mdx Mice. Published in the Journal of Dietary Supplements.
Summary. This is a mouse study. Mice that were genetically created to have muscular dystrophy were given Protandim at a dosage that was similar to what is recommended for humans. After 6 months of use, the mice that were given Protandim showed a 46%reduction in the free radical breakdown of fat (this is called TBARS in the study. TBARS stand for ThiobarBituric Acid Reactive Substances). The greater the TBAR level, the greater free radical damage. Thus, reducing TBARS is taken to be a good thing.
Study Name:The chemopreventive effects of Protandim: modulation of p53 mitochondrial translocation and apoptosis during skin carcinogenesis. Published in the journal PLoS One.
Summary: This is a mouse study. Interestingly the word “mouse” never appears in the summary of this study. Protandim reduced damage to the mitochondria of the mouse cells.
The mitochondria, often called the “powerhouse” of the cell, makes energy —and makes free radicals in the process. The mitochondria is a major area of anti-aging research.
Summary. This is a rat study. Researchers wanted to see if Protandim helped pulmonary blood pressure. After 6 weeks, Protandim did not reduce pulmonary artery blood pressure or the number of lung lesions.
The researchers did say that “our data point to a cardioprotective effect of Protandim.” But, this is a vague statement. Here's why:
In the study, the researchers list 4 things that they say Protandim did— but nowhere in that list did I see the word “significant.” The omission of this word is huge because it could mean that the effects observed might not necessarily be due to Protandim.
Some may say I am nitpicking here, however the holy grail of scientific research are effects that are deemed “significant” —in other words, effects that are not due to random chance. The omission of the word “significant” reduces the importance of this study in my opinion.
2009 Protandim Research
Summary: This is a mouse study.
Summary: This is a test tube study. Cells treated with Protandim showed significant increases in glutathione, an antioxidant compound. This is the study that LifeVantage lists as “proof” that Protandim increases glutathione levels by 300%. It may raise glutathione 300% in a test tube, but what about in people? As far as I can tell, there is no proof of this.
This study is also cited as the “proof” LifeVantage as to why people can't save money by just taking the individual ingredients in Protandim.
2006 Protandim Research
This is a human study. In this investigation, 39 healthy men and women, age 20-78 years were given Protandim (675 mg per day) for between 30 and 120 days. Let's review the results of this study:
1. Protandim caused a significant increase in the antioxidant superoxidant dismutase (SOD) in red blood cells.
2. There was a non-significant rise (4.9%) in uric acid. Uric acid, besides being bad for gout, is an antioxidant. Might Protandim have raised uric acid levels as a result of its ability to increase antioxidant enzymes? I don't know.
3. No change in CRP levels was seen.
4. No change in HDL, LDL or triglycerides were seen.
5. Interestingly, greater free radical breakdown of fat (higher TBAR levels) was seen in those who took the antioxidant supplements vitamin C and E than those who did not. In other words, antioxidant vitamins did not help, but were in fact, bad for the people.
The finding that antioxidant supplements might be bad for us is not new. Other research has shown antioxidant supplements reduce the body's natural antioxidant defenses.
Note in the study above, Protandim didn’t reduce CRP levels. CRP is a measure of cellular inflammation. I feel this clashes with claims by distributors that Protandim reduces inflammation.
My Thoughts On The Research
After looking over the Protandim studies, 2 things occurred to me that I wanted to point out:
First. of all the Protandim studies I found, only 3 were conducted on humans. These studies are:
- The 2006 study (click to see study)
- The 2012 study (click to see study)
- The 2016 study (click to see the study)
All other Protandim research has been conducted in either test tubes or lab mice or rats. Also, of those studies, both the 2012 study and 2016 noted that Protandim didn’t work.
That leaves only 1 human trial (from 2006) showing Protandim might be beneficial to humans.
Here is a summary of Protandim research by year
|Study Year||Type of Study|
|The Effect of Protandim Supplementation on Athletic Performance and Oxidative Blood Markers in Runners||People|
|Longer lifespan in male mice treated with a weakly estrogenic agonist, an antioxidant, an α-glucosidase inhibitor or a Nrf2-inducer||Mice|
|Upregulation of phase II enzymes through phytochemical activation of Nrf2 protects cardiomyocytes against oxidant stress||Mouse heart cells|
|Antioxidants for the treatment of patients with severe angioproliferative pulmonary hypertension?||Rats|
|Phytochemical Activation of Nrf2 Protects Human Coronary Artery Endothelial Cells against an Oxidative Challenge||Test tube|
|Protandim does not influence alveolar epithelial permeability or intrapulmonary oxidative stress in human subjects with alcohol use disorders.||People|
|Oxidative stress in health and disease: the therapeutic potential of Nrf2 activation.||Test tube|
|The Role of Manganese Superoxide Dismutase in Skin Cancer||Mice|
|Protandim attenuates intimal hyperplasia in human saphenous veins cultured ex vivo via a catalase-dependent pathway.||Test tube|
|The Dietary Supplement Protandim® Decreases Plasma Osteopontin and Improves Markers of Oxidative Stress in Muscular Dystrophy Mdx Mice||Mice|
|The Chemopreventive Effects of Protandim: Modulation of p53 Mitochondrial Translocation and Apoptosis during Skin Carcinogenesis||Mice|
|Chronic Pulmonary Artery Pressure Elevation Is Insufficient to Explain Right Heart Failure||Rats|
|Protandim, a Fundamentally New Antioxidant Approach in Chemoprevention Using Mouse Two-Stage Skin Carcinogenesis as a Model||Mice|
|Synergistic induction of heme oxygenase-1 by the components of the antioxidant supplement Protandim.||Test tube|
|The induction of human superoxide dismutase and catalase in vivo: a fundamentally new approach to antioxidant therapy.||People|
Second. The earliest (and presumably the first) Protandim study I found was from 2006. That study was conducted in humans. Why then, did researchers abandon humans and opt instead for investigating Protandim in rodents and test tubes for several years?
Can You Make Your Own?
From the summary of ingredients above we know how much of each of the ingredients is in Protandim. As such some might wonder if they could just take the individual ingredients and save money? The product website says that the special way in which Protandim is made means people would not get the same benefits if they just took each ingredient individually. As “proof” of this, they state that “A scientific peer-reviewed study shows that Protandim produces a 300 percent increase in the antioxidant glutathione.”
I believe this refers to a test tube study published in 2009 and not a study of humans. No human clinical studies comparing the effects of Protandim to its individual ingredients can be located.
Taking 1 pill would be more efficient than taking 5 pills. But, is it better? I can't say either way.
Protandim And Weight Loss
There is no good evidence that Protandim helps people lose weight. As you can see from all the studies listed above, not one of them was about weight loss. While lack of research does not necessarily mean something does not occur, I suggest people ask real research (not testimonials) before believing such claims.
Protandim And Multiple Sclerosis
Multiple sclerosis (MS) is caused by damage to the protective covering of nerve cells. While the process of the damage is due to an autoimmune disorder (the immune system attacks a part of the body – in this case the nerve cells), this damage is thought by some to be the result free radicals. Some have put forth the idea that disruption of free radical stress – via stabilizing Nrf2 (the stuff Protandim is supposed to improve) might help MS.
So is there any proof that Protandim helps MS? While I was not able to discover any published research, there was an investigation that was presented in 2011 at the 5th Joint triennial congress of the European and Americas Committees for Treatment and Research in Multiple Sclerosis Amsterdam, The Netherlands. The title of the presentation was: Nrf2 activators: a novel strategy to promote oligodendrocyte survival in multiple sclerosis?
Oligodendrocytes (oly-go-den-dro-sites) form the protective covering of nerve cells― the covering that is destroyed in MS.
In this study, researchers treated rat and human oligodendrocytes with several compounds ― one of which was Protandim ― and then exposed the cells to a chemical to create free radical damage.
The researchers wanted to see which compound increased Nrf2 related antioxidant enzymes the most in response to the free radical chemical exposure. These researchers noted that Protandim was seen as “the most potent inducer” of Nrf2 antioxidant enzymes defenses.
This is an intriguing study but it does not seem to have been published yet. Published studies tend to carry more weight than unpublished research in the scientific community.
There is also some evidence that stimulating Nrf2 antioxidant pathways might reduce cellular inflammation via inhibition of NFkb. Inhibition of NFkb is also something that another supplement – called Anatabloc – is supposed to do. If this is true, might a cocktail of Protandim and Anatabloc help multiple sclerosis symptoms? I am, of course, speculating here, but it's an interesting question that I hope someone looks at.
For more information, see my Anatabloc review.
Another herbal anti-inflammation supplement I've reviewed is Zyflamend so see this review for additional information.
Protandim And ABC Primetime
In 2005 Protandim was featured on ABC's Primetime news show. In that segment, ABC correspondent John Quinones met with Dr. Joe McCord, who is one of the main Protandim researchers. Dr. McCord is a respected researcher. According to his Wikipedia page, as a grad student, Dr. McCord was involved with the seminal discovery of Superoxide Dismutase, an important free radical savaging enzyme. He is a great scientist with many accomplishments. He is also a contributing author of many of the Protandim studies listed above.
In the Primetime Protandim segment, John Quinones gets a blood test to measure his TBAR level (an indicator oxidative stress). He's given Protandim for 2 weeks and then returns to the lab where he has his blood tested again. Dr. McCord tells John Quinones that Protandim caused a “45% reduction” in oxidative stress and goes on to say that this is the level seen in a “newborn baby”.
Question: Since 2005, have any independent labs tried to reproduce the results of the ABC Primtime news segment? In other words, give Protandim to somebody for 2 weeks and measure TBAR levels before and after Protandim use?
The Primetime segment is interesting. It's now several years old. I wish Primetime would do a follow up story.
Does Protandim Have Caffeine?
According to the product website, each tablet has 1.8mg of caffeine. That's a lot less than is in a cup of coffee and most energy drinks. I don't think this small amount would keep people up at night, but because we are all different it might be wise to not take it close to bedtime.
Protandim Side Effects
I think Protandim is very safe. I am not aware of any side effects from using it. That said, here are a few things people might want to think about.
One study noted that Protandim might raise uric acid levels (by only 4.9%). This might be of interest to those who have gout. For those who have gout, there is evidence that eating cherries or drinking cherry juice can help. Here is my review of Tart Cherry Juice for those who want to see more about this.
On the Protandim FAQ website they also warn against using the product if you are undergoing chemotherapy or radiation therapy for cancer. This is likely because of the unknowns of combining antioxidants some cancer therapies. If you have cancer or are getting treatment for it, ask your doctor. I'm glad the company informs people about this.
In addition, they stress the importance of talking to a doctor if you have any autoimmune disease like arthritis or Type I diabetes. I'm not aware of any problems with Protandim – in anyone – but I appreciated the company mentioning this too.
How To Measure Your TBARS
Remember that TBARS are a measure of free radical damage (oxidative stress) of cells. Protandim is said to reduce TBARS.
The TBAR test is also called a Lipid Peroxidase test. It costs about $200 to have the test done by a doctor. For those who really want to know if Protandim is working or not, getting this test done first—and a month later— might be a good thing to do. I'm not sure if insurance covers the test or not. Talk to your doctor for more information on this.
Aged Garlic Extract also has some evidence it might reduce TBARS, see that review for more information.
What Is TrueScience Anti-Aging Cream?
TrueScience Anti-Aging Cream as this is another product sold by LifeVantage. On LifeVantage.com they say this:
” Its powerful anti-wrinkle formula boosts six skin-rebuilding essentials and contains the 11 ingredients described as the most effective in improving skin tone, texture and appearance. Unlock the science of anti-aging and unlock the secret of a younger-looking you with TrueScience Anti-Aging Cream.”
While the statement above sounds impressive, it's actually rather vague. For example:
- “Skin building essentials” is meaningless. How does it build the skin and what makes the ingredients “essential?”
- Also, who “described” the 11 ingredients as “most effective?“
- “Unlock the science” makes no sense I didn’t see any scientific studies on TrueScience cream that proves it actually works.
Protandim has research, but I'm not aware of any published clinical studies on the TrueScience Anti-Aging cream.
Protandim For Dogs?
In January 2013, LifeVantage Canine Health was announced. According to the LifeVantage website, this product contains the same ingredients as Protandim – and it also has omega 3 fatty acids and collagen. The website goes on to say that:
“Reducing oxidative stress in dogs may reduce many of the disorders associated with aging in canine.”
While this may be possible, I have to ask the question, where is the proof? As can be seen from my summary of Protandim research above, there doesn't seem to be any research of Protandim that used dogs. The LifeVantage website likewise does not list any studies showing that Protandim helps dogs either.
It's possible that LifeVantage has unpublished research on the effects Protandim and dogs, horses and other animals. I'm not sure either way. I am not an expert on supplements for dogs or other animals, so I suggest speaking to a veterinarian who can likely give the best answer on whether Canine Health is right for your dog.
Protandim vs. Elysium Basis
Basis by Elysium is a popular anti-aging supplement that contains very different ingredients from Protandim. One for those ingredients, seems to also improve NFR2 levels, like protandim. So, which one is better? Interesting question and I dont feel the research is there yet to give a definitive answer.
See the Elysuim Basis Review for more insights.
How Much Is Protandim?
According to the Protandim.com website, a one month supply (30 capsules) costs $50 retail. If you order it through a LifeVantage distributor, it costs $40. That means over the course of a year, Protandim will cost between $480 to $600. Shipping and tax may be extra. I can't tell from the Protandim website. If you only want to order 1 bottle to try yourself, you can get it on Amazon too.
For the Canine Heath Protandim, the LifeVantage site lists a price of $30 per month retail and $25 per month if you buy it through a Protandim distributor.
Does Protandim Work?
This is the big question. While I'm very intrigued at the prospect of something that might slow down aging, I'm not sure if Protandim works or not. Even though there are interesting studies on Protandim, I think we need more research. Most of the evidence I saw in support of it stems from test tube studies and lab animal research. I'm looking forward to more human-based research.
Here is Protandim on Amazon for those who want to see what others have said.