The #1 Dietary Risk Factor is Not Eating Enough Fruit

Inhibiting Platelet Aggregation with Berries

The Global Burden of Disease Study published in 2012, is the most comprehensive and systematic analysis of causes of death undertaken to date, involving nearly 500 researchers from more than 300 institutions in 50 countries, and starting with almost 100,000 data sources. What did the researchers find? Here in the U.S., they determined that our biggest killer was our diet. Number 1 on their list of the most important dietary risks was not eating enough fruit, responsible for an estimated 4.9 million deaths a year around the world.

According to the Union of Concerned Scientists: “If Americans ate just one more serving of fruits or vegetables per day, this would save more than 30,000 lives and $5 billion in medical costs each year.” One antidote for individuals is easy, painless, and even pleasurable: exploit the multiple nutritional and protective benefits of fruits and vegetables.

One way plants protect us may be their antiplatelet effects. Platelets are what trigger the blood clots that cause heart attacks and most strokes. And beyond their obvious function in blood clotting, platelets are now considered to play a pivotal inflammatory role in the hardening of the arteries in the first place, and in allergies, rheumatoid arthritis, and even cancer.

Normally, under healthy conditions, platelets circulate in a quiescent, inactive state. But once they become activated, they can emerge as culprits in inflammation. Platelets transport a vast amount of inflammatory chemicals, and upon activation they release these chemicals, which can recruit the inflammatory cells that form the pus pockets within our arterial walls that can eventually burst and kill us.

This involvement of platelet activation in atherosclerosis development is well established. We’ve long recognized the platelets’ role in the final stages; however, a growing body of data indicates that platelets may also play an important role in the initiation and propagation of atherosclerosis in the first place. How can we prevent the excessive activation of platelets? It’s generally recognized that platelet hyper-reactivity is associated with high levels of cholesterol circulating in the blood; so we can cut down on foods that have trans fats, saturated fats, and dietary cholesterol.

We can also eat more fruits and vegetables. For example, different varieties of strawberries have shown a significant antiplatelet effect in a petri dish and in people. How did researchers figure it out? In my video, Inhibiting Platelet Aggregation with Berries, you can see a platelet in a resting state, packed with little round granule grenades of inflammatory chemicals, which fuse together and are released when the platelet gets activated. Because resting and activated platelets look so different, we can just take blood from people and count how many are resting and how many are activated before and after people eat more than a pint of strawberries every day for a month. From just adding strawberries to people’s diets, there’s a small but significant drop in the percentage of activated platelets circulating throughout their bodies.

Other berries had a similar effect, even at a more modest two servings a day. Drinking orange or grapefruit juice doesn’t seem to help, but purple grape juice successfully reduces platelet activity on the same order that aspirin does.

Studies have shown that daily aspirin can reduce heart attacks and strokes; however, aspirin can also cause severe gastrointestinal disturbances and bleeding problems, and so should not be used for the primary prevention of heart attacks and stroke as the benefits don’t clearly outweigh the serious risks. It’s nice to have safe, side-effect free alternatives.

One of the ways plants help keep platelets in their place may actually be their aspirin content! See Aspirin Levels in Plant Foods. Why would a plant make a human drug? It’s so cool, check out Appropriating Plant Defenses.

Is the Standard American Diet really so bad that we could save 100,000 people by just getting up to minimum fruit and veggie recommendations? Even cynics might be surprised: Nation’s Diet in Crisis. Even more plants may cut deaths even more, though. See One in a Thousand: Ending the Heart Disease Epidemic.

For more on lowering cholesterol see my video Trans Fat, Saturated Fat, and Cholesterol: Tolerable Upper Intake of Zero. And it’s never too early to start eating healthier. Check out: Heart Disease Starts in Childhood. Heart disease may be a choice. See: Cavities and Coronaries: Our Choice.

Berries are the healthiest fruits, shown to maintain our brain power (How to Slow Brain Aging By Two Years) and improve our immune function (Boosting Natural Killer Cell Activity). That’s one of the reasons we want to eat Antioxidant Rich Foods With Every Meal.

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 Death, More Than an Apple a Day, From Table to Able, and Food as Medicine.

Image Credit: Michael Stern / Flickr

  • Dommy

    And the Nutritional good news just keeps on comin’!
    Thanks, Dr. Greger.

  • Meadowlark74

    How much is a serving?

    • VegGuy

      A serving of fruit is 1 medium fruit, 1/2 cup fruit or 1/4 cup dried fruit.

  • Nikocado Avocado

    If the #1 Dietary Risk Factor is Not Eating Enough Fruit, does this mean we should consume an All-Raw, Fruit-Only diet? How much fruit is recommended to lower these risks?

    • VegGuy

      In his book, “How Not to Die” Dr. Greger recommends eating 1 serving of berries and 2 servings of additional fruit per day. Vegetables, nuts, beans and grains are also part of a healthy diet as each supplies its own set of unique and powerful nutrients.

    • Tom Goff
  • guest

    The case for fresh whole fruit is undisputed, but I hear arguments both for and against dried fruit, which contains a lot more sugar as a percentage of the total weight. Can somebody who has studied this issue shed light on it? Thanks

    • baggman744

      A cut & paste: In its purest form, dried fruit is just fresh fruit with the water removed. Dehydration, in fact, causes some nutrients to become more concentrated. A 2005 study in Journal of the American College of Nutrition revealed that antioxidants in dried cranberries, grapes, and plums are twice as potent as those in the fresh fruits.

      But keep this in mind before launching a dried-fruit diet: A dried apricot is a fraction of the size of a fresh one, but the two pack the same number of calories and amount of sugar. “We eat with our eyes, so we’re likely to consume more pieces of dried fruit than we should,” says Chrissy Wellington, a nutritionist in Lenox, Massachusetts. A cup of fresh fruit makes up one portion. When eating dried fruit, have a smaller helping—for example, a quarter cup of raisins.

      Watch for added sweeteners (sugar, corn syrup), particularly in tart fruits, like cherries and cranberries. Also, take note of the ingredient list: Only the fruit should be listed. Look for packages that say “no sulfites,” a preservative that maintains color. Dried fruit shouldn’t look like the original; while it might not be pretty, brown and shriveled is your best bet. Remember: Dried fruit is not candy, so it shouldn’t taste like it is.

    • Thea

      guest: I think baggman744’s post has some good points. I also think it is worth taking a look at the NutritionFacts’ videos on dried fruit is worth taking a look at:
      At least some dried fruit can be very healthy. And I know that there is another video on raisins coming out in the next volume. Stay tuned…

  • Mery Daae

    Hi doctor, please make some more info on Chronic Fatigue Syndrome and which foods from a plant based diet to focus on to tackle its effects. thank you for your amazing work, it’s changing my life!

  • baggman744

    You know you’re secure in your manhood when you bring a boat load of sliced fruit to watch a football game with friends. Started doing that 20 years ago. They were all eating chips, dip, pretzels, etc. Now, they’re asking me how I stayed in shape (i.e., not overweight) into middle age… DAH!

    • herrschobel

      lol…you just made me laugh out loud in the office…i am totally with you !

  • vlp

    Can the berries be cooked? I freeze a lot of blackberries from our organic garden, but I like to warm them up on the stove in the morning before I put them on my oatmeal. Do they still have the same antioxidant power?

    • mbglife

      I recently read that if you steam blueberries just a little you’ll get more antioxidants when you eat them. So I looked for that citation but couldn’t find it. But I did find this article on an Italian study which says you can cook them in different ways for more potency. However, blueberries aren’t blackberries and I don’t know if the results would be the same. For example, in his new book (p.294), Dr Greger says that black currants lose up to 97% of their anthocyanins when you make them into jam, which is mostly cooking.

  • Joe Caner

    That’s berry good news. I love fruit. I will have to eat an additional four or five servings of fruit then.

  • jinsight

    If I meet the daily dozen and need more calories due to the amount of work I do, what is the priority among the daily dozen for eating? Should I eat more grains or more nuts or more fruit or more vegetables or more beans or some combination? If a combination, what is the priority or percentages among them?

    • Thea

      jinsight: I personally wouldn’t stress about it. Dr. Greger described his daily dozen as targets. My (completely lay) opinion is that if you meet your targets and you still need more food, then eat more of whatever food that appeals to you and which is still healthy and in the big categories, ie: beans, whole grains, veggies and fruits. If you are very hungry, you might want to eat more starch-based whole foods (sweet potatoes, beans, etc) to fill you up compared to say a focus on green veggies which are the least calorie dense.

      What do you think?

  • allworld212

    Just recently programmed How Not To Die into my e-reader. I’m beginning to feel like a genius going vegetarian/vegan when I was 22 in 1979. Let me tell you something. For a young athletic male from the African-American community, I can’t tell you what a bold move that was in that time frame with no support base for it all. I’m 59 now. My visitations to the ER and hospitals during my adult life have been only to support family members and friends. Although I’m commonly mistaken for someone in their 40’s, I don’t have a false sense of security. Still need to lose about 10 lbs and get rid of the occasional sodas. and I’m not sure what effect my soy lattes have. But I work out on my rowing machine every other day, and I wonder what your feelings are on the blending devices that have been on the market for the last few years. I’ve been using one the past few years to blend blueberries, spinach, kale and such into drinks. With all the evidence now for plant based diets, why do you think the medical world doesn’t just come out and say GO VEGETARIAN? Do you think it fears the meat industry?

    • Thea

      allworld212: Thanks for sharing your story!
      re: “…why do you think…?” I believe that the general consensus is that there are several reasons. You might want to look at the Tomato Effect video here on NutritionFacts. Also consider that most doctors eat meat, diary and eggs. If they admitted to the science, they would be hypocrites if they kept eating those foods and they don’t want to give those foods up. There is more than just speculation here. This is exactly what happened in regards to smoking. At one point, a great many doctors smoked and they would tell you that smoking was perfectly healthy–despite what the science said at the time.
      Other reasons include cultural and economic. The economic one is interesting because it hits on two levels. One is that our society has a set of economic systems in place that keep meat, dairy and eggs going strong. And this happens at several levels. For example, research dollars are being spent on studies that end up promoting meat dairy and eggs one way or another. (Read the book, Whole by Campbell for more info) Also, as Dr. Greger points out in his book, the US government agency which makes the dietary recommendations is also responsible for promoting agriculture. It’s a huge conflict of interest. The meat, dairy and egg industries get massive subsidies, even if just in the form of getting away with horrific externalities.
      This is all big picture stuff when it comes to economic systems. But there is also the smaller economic issue from a doctor’s perspective – and that is that in America, we don’t pay doctor’s to keep people healthy. We only pay doctors when people are sick. I think that the vast majority of doctors would never consciously harm their patients. I also think there is a strong subconscious force at play when your livelihood relies on a conflict of interest where you get paid for working on sick people. I don’t want this to turn into a doctor bashing opening. SO many of the doctor heroes come to this site. I want this to be a welcoming place for doctors. I just think this issue is also worth mentioning when trying to figure out why doctor’s don’t tell almost everyone to eat whole plant foods.

      • allworld212

        What a tangled web. Thanks Thea.

  • Ilse

    I love fruit BUTTTTTTTT…….. now I hear a lot of : too much fruit is not healthy for : carbs/glucose is ok but not fructose in ANY form, Uric Acid, insuline, triglycerides, pcos,…. and I would like your thoughs on : the 80/10/10 highfruit diet and the Mc Dougall diet (white potatoes). Please also give me an easy mealplan I can follow with breakfast, lunch, snack, diner and what can I put in my tea (honey?). Thanks!

    • Thea

      Ilse: Dr. Greger has a video on how much fruit is safe to eat. I think the answer was that it was ok to go as high as 10 servings, but you would want to review the video to verify. Also note that while someone might be able to get away with 10 servings, that is not Dr. Greger’s recommendation for an optimal diet. Dr. Greger recommends one serving of berries and three servings of other fruits each day.
      NutritionFacts also has a video on a sweetener called erythritol (sp?) that you should look up. It could be a great addition to your tea.
      As for meal plans, if you are able to get a copy of Dr. Greger’s book How Not To Die, part 2 could provide you with a lot of great information on how to proceed practically. You might also check out one of Dr Greger’s (and my own favorite!) recommendations for meal plans: PCRM’s free 21 Day Kickstart Program. That program includes grocery lists, meal plans, recipes, cooking videos, inspirational messages, and a forum moderated by an RD that will provide you with all the practical advice you could need to get started. If you are interested, click the green button on this page:

      Hope this helps.

  • Ilse

    oh yes, my question below : anyone can send me info at : Reference : Thanks

  • irah

    Berries are great foods, but I have yet to find a comparison for berries that are useful as everyday additions to oatmeal and breakfast bars or snack mix. It would be great to have a printed list including fat, carbs, fiber, sugars, antioxidant rating and any other useful notes. If it can’t be found for sale with on the first page of a web search, then it need not be on the list.
    Thanks to all who are creating the content on this site