Dean Pomerleau Posted May 9, 2016 Report Share Posted May 9, 2016 All,Over on this thread about the hazards and benefits of a fruitarian diet we've talked (and debunked) about the concern that some so-called nutrition experts have about fructose, even in whole fruit. I was surprised to see that neither in that thread nor anywhere else I could find have we discussed this study . With this post I will remedy that. It's a real winner and I don't mean that facetiously.My only complaint is that it was a small study, involving only 10 people (8 men and 2 women) who were "prepared to eat a large amount of leafy vegetables" - perhaps they couldn't find too many subjects...The participants were healthy folks, average age ~38 and average BMI ~25. That had each subject follow three different diets for two weeks each - "Vegetable Diet", "Starch Diet" and "Low-fat Therapeutic Diet" so as to serve as their own controls. All meals were prepared for each subject and delivered in pre-weighed quantities to them twice weekly. Here are the specific foods eaten for the three diets: Note for the "Vegetable Diet", there were three different days of meals that subjects ate in rotation, while for the other two diets subjects ate the same thing every day for the entire two weeks. Also note that it's not clear from the text whether the olive oil in the starch or low-fat therapeutic diets was extra virgin or not.Here is a high level nutrition breakdown of the three diets: What's noteworthy is that the Vegetable diet looks remarkably similar to my own, whole food, plant-based diet - except for the fact that I eat a wider variety of fruits and vegetables, as well as more nuts, and therefore more fat & calories. Here are a few facts about the vegetable diet from the full text of the paper: This very high intake of fruit and vegetables translated into 63 servings per day for a 2,500 kcal diet (Table 1) It was 18% protein (entirely from plant sources), 22% fat (half from MUFA), and 60% carbs It contained almost 140g of fiber per day The total weight of food was 5.1 kg / day (~11 lbs) The fecal weight during the vegetable diet was over 900g/day (~2lbs) Yup, that's a diet after my own heart. In fact, I'd consider it nearly perfect except I'd replace some of the "chunky" veggies with "leafy" ones, add some omega-3 from walnuts/flax, and of course someone eating this way would need to supplement with at least B12 in the long term.So what did they find?Not surprisingly (to me anyway) the starch diet beat the low-fat therapeutic diet, but the vegetable diet kicked both their butts when it came to markers of cardiovascular health - which was the focus of the study. Here is the time course of changes to total cholesterol, Tot-chol:HDL , LDL:HDL, and APOB over the two weeks on each of the three diets: As you can see from those graphs, and the summary changes below, on nearly every metric the vegetable diet beat the other two: The only thing that the vegetable diet didn't excel at was reducing triglycerides. Note that it didn't raise triglycerides, despite all that fructose, but it didn't reduce them like it reduced all the other CVD indicators.Finally, one more thing the vegetable diet excelled at - satiety: With the maximum satiety rating as 3.0, satiety ratings were highest on the vegetable-based diet (3.0) compared with the starch-based (1.9) and low-fat diets (0.7) and related to the daily weight of food consumed (vegetable-based, 5.1 kg/d; starch-based, 1.9 kg/d; and low-fat therapeutic diet, 2.0 kg/d). So if you are ever asked how you know your crazy whole food, plant-based diet is healthy, or how you know that all that fructose isn't spiking your triglycerides and trashing your liver, beyond sharing your own blood tests, I'd say this is the best study I've found to offer as evidence.--Dean---------- Metabolism. 2001 Apr;50(4):494-503.Effect of a very-high-fiber vegetable, fruit, and nut diet on serum lipids andcolonic function.Jenkins DJ(1), Kendall CW, Popovich DG, Vidgen E, Mehling CC, Vuksan V, RansomTP, Rao AV, Rosenberg-Zand R, Tariq N, Corey P, Jones PJ, Raeini M, Story JA,Furumoto EJ, Illingworth DR, Pappu AS, Connelly PW.Full text: http://sci-hub.cc/10.1053/meta.2001.21037We tested the effects of feeding a diet very high in fiber from fruit and vegetables. The levels fed were those, which had originally inspired the dietary fiber hypothesis related to colon cancer and heart disease prevention and also may have been eaten early in human evolution. Ten healthy volunteers each took 3 metabolic diets of 2 weeks duration. The diets were: high-vegetable, fruit, and nut (very-high-fiber, 55 g/1,000 kcal); starch-based containing cereals and legumes (early agricultural diet); or low-fat (contemporary therapeutic diet). All diets were intended to be weight-maintaining (mean intake, 2,577 kcal/d). Compared with the starch-based and low-fat diets, the high-fiber vegetable diet resulted in the largest reduction in low-density lipoprotein (LDL) cholesterol (33% +/- 4%, P <.001) and the greatest fecal bile acid output (1.13 +/- 0.30 g/d, P =.002), fecal bulk (906 +/- 130 g/d, P <.001), and fecal short-chain fatty acid outputs (78 +/- 13 mmol/d, P <.001). Nevertheless, due to the increase in fecal bulk, the actual concentrations of fecal bile acids were lowest on the vegetable diet (1.2 mg/g wet weight, P =.002). Maximum lipid reductions occurred within 1 week. Urinary mevalonic acid excretion increased (P =.036) on the high-vegetable diet reflecting large fecal steroid losses. We conclude that very high-vegetable fiber intakes reduce risk factors for cardiovascular disease and possibly colon cancer. Vegetable and fruit fibers therefore warrant further detailed investigation.PMID: 11288049 Link to comment Share on other sites More sharing options...
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