BareBones Barbell Club of TucsonBare Bones Barbell Club
Contact Us For: strength training, power lifting, Olympic Lifting, private coaching

Find us on Facebook!

Post Categories

CrossFit Journal

Crossfit Works, Inc., Fitness Centers,
Tucson, AZ

Fruit is good for you, right?

Some people seem to approach the Paleo diet from a sort of tunnel vision approach.  It goes like this:

“Since cavemen could have found honey, honey is Paleo.  Since there was fruit in the pre-agricultural era, it is Paleo.  If these foods are technically Paleo I can eat as much of them as I want to.”

Ummm, wrong.  How often did your average little tribe of hunter-gatherers find a honey stash?  How long is the season for most fruits?  Banana a day, 365 days a year?

Lots of you have been told to be concerned about your cholesterol levels and thus to keep an eye on your fat intake (baseless, bad information).  Did any of your physicians mention to you the effect of fruit and/or fructose on your cholesterol levels?  I bet not.  Check this out:

“While research has been accumulating that document the adverse health effects of fructose, a carefully-conducted collaborative research study conducted by a University of California-Berkeley group has finally closed the lid on the fructose question.

Compared to glucose, fructose induced:

1) Four-fold greater intra-abdominal fat accumulation¾3% increased intra-abdominal fat with glucose; 14.4% with fructose. (Intraabdominal fat is the variety that blocks insulin responses and causes diabetes and inflammation.)

2) 13.9% increase in LDL cholesterol. It also  doubled Apoprotein B (an index of the number of LDL particles).

3) 44.9% increase in the dreaded small LDL, compared to 13.3% with glucose.

4) While glucose (curiously) reduced the net postprandial (after-eating) triglyceride response, fructose increased postprandial triglycerides an incredible 99.2%.

The authors propose that fructose metabolism, unlike glucose, is not inhibited (via feedback loop) by energy intake, i.e., it’s as if you are always starving.

Add to this the data that show that fructose increases uric acid (that causes gout and may act as a coronary risk factor), induces leptin resistance, causes metabolic syndrome (pre-diabetes), and increases appetite, and it is clear that fructose is yet another common food additive that, along with wheat, is likely a big part of the reason Americans are fat and diabetic.

Fructose is concentrated in high-fructose corn syrup, comprising anywhere from 42-90% of total weight. Fructose is also half of sucrose (table sugar); thus, table sugar can be expected to yield many of the same effects. Fructose is also fruit sugar; among the worst culprits are raisins (30% fructose) and honey (41% fructose).”

Dr. William Davis

For those of you wondering, agave nectar, honey and fruit all have fructose as their sugar.  Table sugar is half fructose.  Please remember that eating Paleo means more than just avoiding a particular list of foods.  It also means taking in foods in amounts that are appropriate.  Lots and lots of fruit every day is not on the Plan.

Don’t forget, Intro to Paleo, nutrition lecture next Wed, July 28 at 7pm.  Free and open to the public.

If you liked this post, say thanks by sharing it:

13 comments to Fruit is good for you, right?

  • Prof. Steve’s Road Report:
    Greetings from Milwaukee. Here’s what I did today at CrossFit Milwaukee. Thanks to Alex for his coaching.
    WarmUp:
    5 min. jump rope
    15 pullups
    2 lengths jog
    15 dips
    2 lengths hi knees
    15 KTE
    2 lengths butt kicks
    3 rnds: OHS 10x, pass thrus 10 x

    Warrior Walk (55#/35#)
    DB OH Walk 45′
    10 Pushpress
    Rack Walk 45′
    10 Front Squats
    Farmers Walk 45′
    10 Hang Squat Cleans
    Walrus Walks 45′
    Renegade Rows (10 each side)
    5 min rest, then 1 more round.

    My time=19:27 @ 35 lbs. puke.

    Miss you guys!!!

  • Crandall

    Jen I love reading these types of posts. Especially todays, since I had mixed berries with my eggs and sausage this morning and mixed melons/pineapple with my spicy tuna on salad at lunch. I’ll have to cut back on the fruits I guess. (me with my head down)

    Stephen, that sounds like a lot of walking, in a brutal kind of way. Keep it up. See you when you return.

  • jerry

    Ummm…sorry to be devil’s advocate (again), but I tend to read these topics a little differently. That quoted text seems to be discussing the potential adverse effects of fructose (most notably high fructose corn syrup…nasty stuff) compared to glucose…not necessarily fruit (which has a natural form of fructose). I’d argue that most fruit does not have high percentages of fructose. Plus, let’s not forget all the benefits of fruit…things like essential vitamins, antioxidants and micro-nutrients, in addition to the association between fruit intake and the reduced risks of various cancers and cardiovascular disease. But as Jen mentioned, balance is key as well as the timing of consumption (when liver glycogen levels are likely to be low, I believe).
    I’ll stop there…please don’t cancel my membership, Jen.

  • Ron

    I’m glad to hear both sides. Fruits have significantly replaced sweets, pastries, soda and bread for me. I’m working toward the next level. My wife says to try some sliced tomato instead of a two nectarines with lunch.

    The struggle continues.

  • Jen

    Jerry, fructose is fructose. There is no difference between “natural” and otherwise. It is one of the monosaccharides. The only difference between high fructose corn syrup and raisins is about 20g of fructose/100g of food. High fructose corn syrup is a more dense and concentrated source of fructose but it is the same thing. High fructose corn syrup does come from corn. There are many people in our gym eating fruits very high in fructose at quite large quantities in a way they would not, these days, drink a blue drink sweetened with high fructose corn syrup. But the reality is that for some people it is the same amount of fructose.
    Jerry, don’t put words in my mouth. I was not making and argument against eating fruit. I didn’t say not to eat fruit. Yes, of course fruit has vitamins and minerals. When I post a study or a piece of information on the website it isn’t to throw down a be all and end all assessment. A clip from a study is only a little bit of important information to consider. In fact in my post I simply said to consider the amounts of fruit. And I will of course remind everyone that vegetables are wonderful sources of vitamins, minerals and antioxidants without such a dollop of fructose. No devil’s advocate is required in this situation. In fact, Ron now thinks there are “two sides” to this issue. There are not two sides at all. There is, exactly what Ron said- Fruit is way better than sweets and soda and bread, but maybe it is possible to do even better. And for those of you with certain health issues, digestive disturbances, etc… a HIGH FRUIT diet is not a good idea. There isn’t a need for a graduate school debate. This isn’t a for and against issue. As always it is a situation of looking at what you need for your health and making choices that bring you nearer to it. I trust that everyone who reads this website knows that there is always more to a training or nutrition issue than one study. Smart folks out there. And I love to have any type of conversation or discussion anyone wants to have. In fact, if you teach me something new about nutrition I’ll give you half off next month on your membership.

  • jerry

    Sorry Jen. I truly wasn’t aiming to put words in your mouth. The post was just a little misleading to me and so I was just advocating for fruit, because most people I come across in my work are on the other end of the spectrum and don’t eat enough of it. But you’re probably right that the crowd reading your website isn’t the one needing such a message. I’ll do my best to avoid raising any of my skeptical tendencies in the future. Cheers to all!

  • Breck

    I ate cow heart for lunch today.

    I almost threw up three separate times while chewing and swallowing. The gristle was pretty intense.

    I wouldn’t recommend it.

  • Jen

    Breck-you are the new CrossFit Works Poster Child. Kids-when you grow up, be like Breck. And Jerry, keep up your skeptical tendencies. I will won’t feel loved without them.

  • Ryan

    We all know that paleo-man didn’t have fruit to eat every day because used it all up making delicious pie. Yum! Pie!

  • Bryon

    I don’t want to cause too much of an uproar, but…
    Up in Minnesota during my recent vacation my family and I picked about a gallon of fresh ripe wild raspberries which my brother’s girlfriend made into a delicious pie, with real lard in the (non-paleo) crust. Yum! Pie!

  • Jen

    The benefits of lard far outweight the drawbacks of fruit… and if eating wild raspberries which you have picked is the Paleo approach to fruit. I can always count on Bryon to set a good Paleo example.

  • Marty

    If you are interested in reading the linked study at the source go to:

    http://www.jci.org/articles/view/37385

    You will likely find it interesting that:
    -The folks tested here were 40-72 yrs old and exercised less than 3.5 hrs per week
    -The sugars were provided to the subjects as 3 daily servings of glucose- or fructose-sweetened beverages flavored with an unsweetened drink mix (Kool-Aid; Kraft).
    -During the outpatient portion of the study they were instructed to eat their normal diets and supplement with these additional glucose or fructose calories.
    -Several of the researches were currently receiving income from Bristol-Meyers Squib or Merck
    -The study seemingly focused on the effects of sweetening our foods with all glucose, all fructose, or some other ratio in between. It really doesn’t seem to be looking at the effects of including additional whole fruits in the subject diets.

    I wouldn’t necessarily infer that fruit itself is bad for you or even that “fructose is fructose”. That seems to be like saying sucrose is sucrose or lean protein is lean protein. For example, I believe that chewing on actual sugar cane is going to have a noticeably different result on my insulin response than a spoonful of refined sugar even though I’m pretty sure they are both technically sucrose. If there was an additional test group which consumed the equivalent or greater amount of fructose through REAL fruit I would venture to guess that the results would be different. I am always suspicious of these isolated nutrient studies and like to read the method and conclusions.

    From my limited research, whole fruit seems to be an efficient and healthy way to top off liver glycogen stores early in the morning, before a workout, or immediately after a workout.

  • John W

    Jen, I’m curious as to how you manage to shame me about my diet from a couple thousand miles away. Truly impressive.

Leave a Reply

 

 

 

You can use these HTML tags

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>