Inhibiting Platelet Activation with Tomato Seeds

Image Credit: Rusty Clark / Flickr. This image has been modified.

Inhibiting Platelet Activation with Tomato Seeds

In the prevention of cardiovascular disease, the consumption of fruits and vegetables is crucial. Preventing the oxidation of cholesterol may be one of the mechanisms by which fruits and vegetables reduce the risk of heart attacks and strokes. However, hyperactivity of platelets is also critically important in the pathogenesis of cardiovascular disease, as I’ve covered before (See Inhibiting Platelet Aggregation with Berries).

In recent years, it has been shown that platelets are not only involved in the arterial clotting process, but also that they play an active role in the inflammatory process of atherosclerosis from childhood. By the end of our teens, atherosclerotic lesions are present in most people living in industrialized societies; and so, suppressing the over-activity of platelets may be beneficial not only for heart disease, but for cancer, allergies, and diseases for which inflammation plays a major role.

The antioxidant properties of fruits and veggies are well known. However, their anti-clotting effects on platelets are less known. Preliminary studies have demonstrated the platelet activation suppressing activity of a variety of fruits and vegetables. They suppress platelet activation so well that they can actually mess up platelet function tests. And, the effects are so long-lasting that fasting the morning of your blood test may not be sufficient.

Out of 16 different fruits tested, tomatoes came out number one. The anti-platelet activation components in tomatoes are water soluble, so we don’t have to eat them with fat; heat stable, meaning we can cook tomatoes without losing the benefits; and concentrated in the yellow fluid around the seeds. This is why tomato pomace beat out tomato juice, sauce, or ketchup. Pomace is basically the seeds and the peel, which the industry throws away, and it may be the healthiest part. And, the more tomato seeds, the better. But this study was measuring platelet activation in a petri dish. Grapefruit came in number two here, and grapefruit juice at least didn’t appear to help when people actually drank it. Would drinking tomato juice actually help?

Platelets of patients with diabetes are characterized by intensified activation; so, 20 diabetics were asked to drink a daily cup of tomato juice for three weeks or a tomato-flavored placebo beverage, and there was a significant drop in platelet activation.

A study done by the Rowett Research Institute, highlighted in my video, Inhibiting Platelet Activation with Tomato Seeds, found this works in healthy people as well. Within three hours of consumption, two tomatoes lowered platelet activation, and six tomatoes worked even better. Also, the effects were more wide-ranging than those of aspirin, in that the tomatoes targeted multiple pathways of platelet activation.

About one in four people are aspirin resistant, meaning aspirin doesn’t work to calm down their platelets, whereas only 3% of study subjects were found to be tomato resistant.

This finding indicates an advantage of the tomato extract’s broad antiplatelet activity profile over single-target drugs such as aspirin. Also, when researchers stuck tubes into people while they were eating tomatoes, they found no changes in blood clotting times, implying that supplementation with tomatoes should not result in a prolonged bleeding times; so, one might get the best of both worlds: less platelet activation without the bleeding risk. But, if tomatoes don’t thin our blood, do they work?

Researchers out of North Carolina State University report that, “consumption of tomato products has been found to be protectively correlated with a lower incidence of acute coronary events, less development of early atherosclerosis, and lower mortality from heart disease.”

If you don’t like tomatoes, kiwifruit recently beat them out in a test tube study of platelet activation. Strawberries may help too, but we have data showing kiwis may actually work in people, and two kiwis appeared to work just as well as three kiwis. It appears to work for green-on-the-inside kiwifruit, and for yellow-on-the-inside kiwifruit. In this case, though, one a day seemed to help, whereas two-a-day did not, which seems a little strange. And, there haven’t been any studies to see if kiwifruit eaters actually have fewer strokes and heart attacks; so, the best evidence for a dietary intervention to decrease platelet activation currently rests with tomatoes.

One of my favorite videos, The Tomato Effect, is actually not about tomatoes at all, but talks about the power of a diet composed entirely of plants to combat the heart disease epidemic. After all, Heart Disease Starts in Childhood.

I do have some others that really do touch on tomatoes, though:

More on kiwis here:

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live year-in-review presentations Uprooting the Leading Causes of DeathMore Than an Apple a DayFrom Table to Able, and Food as Medicine.


Michael Greger M.D., FACLM

Michael Greger, M.D. FACLM, is a physician, New York Times bestselling author, and internationally recognized professional speaker on a number of important public health issues. Dr. Greger has lectured at the Conference on World Affairs, the National Institutes of Health, and the International Bird Flu Summit, testified before Congress, appeared on The Dr. Oz Show and The Colbert Report, and was invited as an expert witness in defense of Oprah Winfrey at the infamous "meat defamation" trial.

34 responses to “Inhibiting Platelet Activation with Tomato Seeds

Comment Etiquette

On, you'll find a vibrant community of nutrition enthusiasts, health professionals, and many knowledgeable users seeking to discover the healthiest diet to eat for themselves and their families. As always, our goal is to foster conversations that are insightful, engaging, and most of all, helpful – from the nutrition beginners to the experts in our community.

To do this we need your help, so here are some basic guidelines to get you started.

The Short List

To help maintain and foster a welcoming atmosphere in our comments, please refrain from rude comments, name-calling, and responding to posts that break the rules (see our full Community Guidelines for more details). We will remove any posts in violation of our rules when we see it, which will, unfortunately, include any nicer comments that may have been made in response.

Be respectful and help out our staff and volunteer health supporters by actively not replying to comments that are breaking the rules. Instead, please flag or report them by submitting a ticket to our help desk. is made up of an incredible staff and many dedicated volunteers that work hard to ensure that the comments section runs smoothly and we spend a great deal of time reading comments from our community members.

Have a correction or suggestion for video or blog? Please contact us to let us know. Submitting a correction this way will result in a quicker fix than commenting on a thread with a suggestion or correction.

View the Full Community Guidelines

  1. I guess a Vitamix would be helpful if one wanted to make whole tomato ‘juice’ or even sauce (cook out the excess water after blending). Don’t have one myself.

    1. You don’t need a Vitamix to make tomato juice or sauce although it’s nice to have it. You can always cook whole tomatoes and it will soften and become a sauce. Also, I don’t want to throw away the water because there is some nutrition in there. I will drink the water or put it in a soup.

      1. The peel and the seeds might cause texture problems for some, though. Vitamix blending maxes everything really smooth and velvety (I guess that’s why they cost so much), as you say – nice to have. If you cook out the water all the heat stable nutrients should be left behind.

        1. Like Dr Greger talked in one of his videos, tomato contains lycopene which will be enhanced greatly when you cook. But you will lose some or most vitamin C when you cook but you can get it from other sources such as other fruits. In another word, lycopene is more important and hard to get than Vitamin C.

    1. Yes, grape seed extract is a health food store product. If I remember correctly, it fights cancer among other things. I don’t have to pollute and drive to the store to get it. It comes from my yard in a handy package-grapes.
      John S

      1. My point is that tomato, grape, watermelon, etc. are now modified so that they don’t have seed. So even if you plant them, depending on the variety, they may not have any or very few seeds. So does that mean they are less nutritious if you eat the whole fruits, skin, meat, juice, a few seeds or none?

        1. I have never seen a seedless tomato whether I buy hot-house, beef steak, cherry, romano, etc. The store hasn’t impacted this either. Smiths, Fred Meyer, Albertson’s, local farmers markets, etc>

          Where are you getting these? Are you trapped in a small mountain town with one supplier or something?

          Also, you can get grapes with seeds as well as seedless.

          Watermelons – even seedless ones have plenty of white and some black seeds in them.

          Seedless in most all produce tends to mean smaller or fewer seeds and not literally no seeds.

          1. OK tomato and watermelon have fewer seeds than the old days. Grape mostly has none. In fact, I just bought some seedless grapes from Trader Joe yesterday. So my question is without the rhetoric that I should buy seeded fruits or not, is that are the seedless fruits less nutritious than their seeded counterparts or is it the same if I eat the whole fruit? Because nutrition may be concentrated in the seeds but when there is none then it should be somewhere else in the fruit and cannot disappear in thin air. That’s logical.

            1. anytime you can consume whole plant foods, seeds or not, it is highly beneficial.

              I wouldn’t be worried about the seeds but when there are grapes being sold but not labeled as seedless then give them a shot and maybe you will get a nutrition boosting bunch of seeds.

              The grapes that I tend to find seeds in are purple/black but that could be a regional thing and maybe lighter grapes or green grapes elsewhere have seeds and dark ones do not.

              In the long run, your health benefit will come from being highly or entirely plant based eating. The seeds being in fruit or not is really going to only be the icing on the cake. However, the less plant based someone is the more benefit they will be getting from eating the seeds as well since they need as much nutritional help as they can get.

              1. I think I understand the question now, Jimmy. I agree with mjs. Whole plant foods are nutrition dynamos. If they don’t have the seeds, they’re good, just not as good. There is less nutrition, but if you won’t eat them with the seeds or can’t get them, they’re still good. I planted ones with seeds on purpose.

                I also never peel apples or potatoes and I eat organic, because that’s where most of the nutrition lies. Throw out the peel, you get much less nutrition.
                John S

                1. I eat the skin of most fruits and vegetables too unless it’s not pleasant to eat such as banana peel (I have tried but don’t like it). I eat also the stem and root. If it is not easy to digest such as beet leaves then I juice it.

              2. MJS, I tend to agree with you more than John (sorry John :)) that when you eat the whole fruit then seed or no seed are the same. Yesterday, I just bought some seedless grapes from Trader Joe and they look dark and very wild, super sweet and it melts in your mouth. So I got the feeling that this is very nutritious grapes but it has nno seed.


                I have a similar question regarding the peel of orange. As you know, the most nutritious part of the orange or any citrus fruit, is the white part of the peel and more than the meat and juice. Because the white part contains pectin which is a very powerful anti-oxidant. The yellow part has no nutrition and it is hard to digest and so I use a vegetable peel to remove the yellow part and then eat the whole orange including the white part of the skin.

                So OK, non organic orange such as Sunkist has very thick skin and a lot of white part while the organic orange from let say Trader Joe is smaller and its skin is thin and there isn’t much white part. So does that mean the organic orange is less nutritious than the non organic counterpart in term of pectin content? I don’t think so.

                  1. I hope that I am right (seed does not matter if you eat the whole fruit) because it makes easier for me to shop (and to plant).

    2. Dr Greger talked about tomato seeds in the above video.

      With regard to grape seeds, it’s a little bit different. It’s still not conclusive about its benefits yet but if one wants to consume them, it seems like the only way is to take a supplement. Because it is the OCP extract part of the seed that is useful and you have to 1) probably consume a lot of grape seeds, and 2) whether or not your body can digest and extract the OCP from eating the seeds. The grape seed extract comes from a lot of grape seeds from the winery.

  2. I have an huge, really huge, crop of tomatoes this year in my garden. I have so many that I do not know what to do with them. Now that I read this article, I know exactly what to do with them…….juice them and get the benefits of controlling platelet aggregation. Thanks Dr. Greger for that tip. You are saving lives.

    1. John, do you preserve the tomatoes by canning to eat them during the year? And if you do then do you have to refrigerate it?

      1. Jimmy, I do not know how to can food from my garden. So, what I don’t eat, I give to my neighbors and the birds and deer in the field. Since I live in South Texas, I can have a garden all year round, so I don’t really need to learn how to can food. I have friends who live near Salt Lake City and they are into prepping, and they know everything there is to possibly know about canning, and preserving food. And, what they do is very, very time consuming. I am busy with other stuff, so I don’t really feel the need to acquire all of those skill sets that my friends in Utah have. There is a high concentration of white tail deer where I live in the country, and I have tamed some of them to come up to me and eat out of my hand.

    2. Field tomatoes are just now coming into season in this area , wow what a taste difference from greenhouse tomato, when will Dr. Greger be doing a video on the nutritional difference between greenhouse grown and field grown? Bet there will be huge difference in nutrition. Enjoy your home growns!

  3. So how much tomato juice would equate to one aspirin? I ask because I, like many people, take one full strength aspirin daily and I would love to stop taking it and try a food instead. I was prescribed the aspirin after a serious blood clot after which I went on a WFPB diet but my doctors at the Mayo Clinic are quite insistent on my continuing with the aspirin.

    1. I would say 2 cups of tomato per day.

      Tomato thins the blood via lycopene which is different from aspirin which blocks something, I forgot. But the objective is to thin blood.

      Lycopene is the chemical that makes the tomato red, according to the National Institutes of Health. You need about 2,310 to 3,000 IU of vitamin A each day, and a cup of tomatoes provides between 41 to 53 percent of your daily recommended intake.

    2. I am not suggesting anyone to take a pill here but the following article from Dr Mercola suggests the dosage from consuming the tomato juice or paste directly. (I know that a lot of people don’t like Dr Mercola here but we talk about sciences and we need to look at all sides of the argument).

      You need 7 mg of lycopene per day. So from the following data, you only need to consume 1/3 of a cup of tomato juice per day which answers Kathryn question from above.

      Product Serving Size Lycopene mg/serving)
      Tomato juice 250 mL (1 cup) 25.0
      Tomato ketchup 15 mL (1 tbsp) 2.7
      Spaghetti sauce 125 mL (1/2 cup) 28.1
      Tomato paste 30 mL (2 tbsp) 13.8
      Tomato soup (condensed) 250 mL prepared 9.7
      Tomato sauce 60 mL (1/4 cup) 8.9
      Chili sauce 30 mL (2 tbsp) 6.7
      Cocktail sauce 30 mL (2 tbsp) 5.9
      Watermelon 368 g (1 slice: 25 x 2 cm) 14.7
      Pink grapefruit 123 g (1/2) 4.9
      Raw tomato 123 g (1 medium) 3.7
      Source: Heinz Institute of Nutritional Sciences,

    3. I think Dr Greger was saying there is more benefit from the whole tomato , a lot of the benefit was the slippery fluid around the seed , which is discarded from a lot of tomato products. Normally the skin and seed of tomato is sieved out of the product and sold to dehydrators and used in various animal feeds.

  4. One of my common snacks at work is a tub of cherry/small tomatoes. I often get the Sugar Plum variety and snack on a pound of them through the day. (I’m doing so right now as I type.)

    Eating the little guys whole means that I get the seeds and the skin. They are not cooked, though. So, I didn’t think I got much out of it other than the normal/typical fruit and veggie benefits. I liked this article because it sounds like I get some extra good things from my little tomato snacks even though they aren’t cooked! :-)

  5. What about people with ITP (low platelet count)? Should they stay away from tomatoes, berries, kiwis? Oh, say it isn’t so!

    1. My understanding is that they inhibit activation – activation of the cascade that causes the sticking together / coagulation of platelets, not the generation of new platelets.

      You should probably ask your dr. about it.

      1. Yes, understood. The question was about whether someone with not too many platelets should be eating things that interfere with aggregation. Most doctors don’t know anything about foods that affect platelet quantity or function.

        1. Beth, did you ever find an answer to this question? I have low platelets and am wondering what to eat – or what to avoid – in order to alleviate this problem.

  6. I?m amazed, I have to admit. Rarely do I come across a blog that?s
    equally educative and amusing, and without a doubt, you’ve hit thee nail on the head.
    The issue is an issue tbat too few people are speaking intelligently about.
    I aam very happy that I stumbled across this
    during my search ffor something regarding this.

  7. I simply desired to thank you so much yet again. I aam not
    sure the things that I could possibly have done in the absence of
    the methods contributed by you about such a
    situation. This has been the scary scenario in myy opinion, buut witnessing the
    specialised manner you dealt with that forced me to leap
    with joy. I will be grateful for this guidance as welol as hope that you really know what an amazing job you are providing teaching the mediocre ones
    ith the aid oof your web blog. Most likely you’ve never got to know anyy of us.

Leave a Reply

Your email address will not be published. Required fields are marked *

Pin It on Pinterest

Share This