Sunday, December 22, 2013

The Oslo Diet Heart Study

Studies Associated with the Trial

The effect of plasma cholesterol lowering diet in male survivors of myocardial infarction. A controlled clinical trial (1966) [1] (no access)
The effect of a cholesterol lowering diet in male survivors of myocardial infarction. (A controlled clinical trial) (1967) [2] (in Norwegian)
The effect of plasma-cholesterol-lowering diet in male survivors of myocardial infarction. A controlled clinical trial (1968) [3]
The Oslo Diet-Heart Study: Eleven-Year Report (1970) [4]
Prevention of coronary heart disease: some results from the Oslo secondary and primary intervention studies (1989) [5] (no access) 

Participants and Diets 

412 men aged 30 to 64, who had previously had a heart attack, were randomised to two groups: an experimental group and a control group.  The control group consumed their regular diet, while the experimental group was instructed to consume a diet low in animal fats and cholesterol and high in vegetable oils.  Dietary information from only 17 participants in the experimental group was reported.  The groups were similar at baseline, except the experimental group had slightly higher blood pressure [3] 

The papers I had access to only had pretty basic information on the diet, which came from only 17 participants in the experimental group 

Energy (kcal)
2400
Protein (g)
92
Fat (g)
SFA/MUFA/PUFA (g)
P/S Ratio
104
22/27/55
2.4
Carbohydrate (g)
Sugar (g)
269
51
Dietary Cholesterol (mg)
264

Results 

Cholesterol levels decreased in the experimental group [3]


The number of major CHD relapses can be calculated using the table below from the total number of CHD relapses - angina.  CHD mortality can also be calculated using the table below from the number of fatal myocardial infarctions (10 vs. 23) and the number of sudden deaths (27 vs. 27) [3].  CVD mortality and total mortality are reported more simply in a paper [4] and the results are presented in my table below. 



Experimental
Control
Major CHD Events [3]
70
91
Total CHD Events (P = 0.011*) [3]
80
120
CHD Mortality [3]
37
50
CVD Mortality (P = 0.09) [4]
38
52
Total Mortality (P = 0.13) [4]
41
55

At the end of the 5 year diet period: “the surviving dieters were advised to adhere to the cholesterol lowering diet in the future. The surviving controls were informed that a reduced fat intake possibly might be beneficial, but they received no detailed dietary instructions.”The men were followed for an additional 6 years to track mortality [4].  After 11 years the mortality is as follows:

 [4]
Experimental
(n=206)
Control
(n=206)
Total Cardiovascular Mortality (p=0.13)
88
102
Other Mortality
13
6
Total Mortality (p=0.35)
101
108

So far, this looks to be one of the more favourable studies for the diet heart hypothesis, but even though I don’t have access to the data other people do.  The meta-analysis by Ramsden, et al discussed how the Oslo Diet Heart Study isn’t a simple omega 6 vs. SFA trial, but rather is multifactorial in favour of the experimental diet:

  • The experimental diet was higher in omega 3.  Meats and eggs were replaced with fish, shellfish and ‘whale beef’.  The experimental group was supplied with considerable quantities of Norwegian sardines canned in cod liver oil, which proved to be popular as a bread spread”.  And also soybean oil has some plant omega 3 
  • The experimental diet was higher in vitamin D, which is a more important source of vitamin D for Norwegians.  The fish and cod liver oil supplied 610 IU of vitamin D 
  • The experimental group was encouraged to eat more nuts, fruits, and vegetables; to limit animal fats; and to restrict their intake of refined grains and sugar 
  • The experimental diet was lower in trans fats.  Paraphrasing from Ramsden, et al: in the two decades before the ODHS, Oslo males had a 7-fold increased incidence of an initial heart attack, which coincided with a rapid rise in partially hydrogenated fish and vegetable oil margarines.  In the control group, about 6.9% of total calories came from these margarines, whereas they were “entirely restricted” in the experimental group

With the trial being so multifactorial in favour of the experimental group I don’t think one should use it as evidence for the diet heart hypothesis or for recommendations for omega 6 to replace SFA.

13 comments:

  1. New 4K Video Folding Drone from Xiaomi the Fimi X8 SE Drone is sure to shake up the drone market. At under $500 this aerial photography drone could become a best seller. If you are looking to get into aerial photography and your budget doesn't stretch to a DJI Drone this Fimi X8 SE could be perfect for you. Long flight time, 3 axis gimbal and 5K range the new Fimi X8 SS Drone.

    ReplyDelete
  2. How do I play PUBG mobile and live stream at the same time? Download Arcade Creative live streamOmlet application and then live stream. It will Stream the game live which you are playing and don’t clear the background process as it will be streaming it in the background.

    ReplyDelete
  3. For the person who lives to play the slots, the advent of bonus slots and feature slots online have opened up a world of exciting gambling opportunity and fun. Will thousands of online sites; you're sure to find several feature slots that will become your favorites.

    The great thing is that you don't have to go anywhere except to your computer to play these exciting feature slots or bonus slots. You just sit back in your favorite chair and have fun. There's plenty of challe...

    ReplyDelete
  4. Fairview's vision is to provide financial freedom to all patrons with credit burdens. We’ll work with you step by step on how to not only improve your credit by analyzing your credit report and helping you to remove the inaccurate marks that are impacting your credit score, but we’ll show you how to budget yourself to make sure you keep your score up providing you with the upper hand when applying for new credit. Call us today (678)-626-1737

    ReplyDelete
  5. You can loss weight by HCG diet for better health without losing your healthy muscles. Come to Bodyology center to get legal HCG hormone for proper weight body.

    ReplyDelete
  6. El Paso SEO We Generate New Revenue for our Clients with Organic Search Engine Traffic. We are El Paso #1 Digital Marketing & SEO Company

    ReplyDelete
  7. If you’re still wondering whether you should keep the halogen headlights of your car or shift to LED highlight bulbs, we’ve got your back. Seriously, should you make this change? How to keep yourself safe when driving and with a moderate budget? Let’s light up your knowledge about car LED headlight bulbs and why you should get yours as quickly as possible.

    ReplyDelete
  8. Farm Feed Systems was established in 1999 and provides specialist feed equipment such as pellet mills and products to various manufacturers throughout the world.

    ReplyDelete
  9. Auf dem Weg in die 5. Dimension erlebt die Erde und die Menschen eine gewaltige Transformation. Bewusstseins Zustände wie bei Astralreisen können dabei entstehen. Portaltage helfen uns, diesen Übergang in die 5. Dimension leichter zu erleben.

    ReplyDelete
  10. Icons for website and web buttons to use in your creative projects, web development, ad campaign, social media pages, and presentations.

    ReplyDelete
  11. We're an business that masters the abilities of making multi-dimensional internet development as well as promotional services for the prestigious customers. We possess separate groups to appeal your marketplace needs for SEO , Social Press High Rates and Customer Friendly Internet Designing. We set our very own standards to be able to break by our personal professionals!

    ReplyDelete
  12. Airport Taxi Dfw is operational Transportation Service for valid client during 24/7. With the sincere motivation airport Taxi DFW keeps the price range within client support. At the same time airport Taxi DFW offers comfortable ride with its skilled drivers. Additionally DFW airport Taxi drivers have smart knowledge about surrounding areas to give the quickest safe passenger care. We serve DFW airport Transportation Service so as to DFW, TX community for seven years with excellent coordination of friendly and timely.

    ReplyDelete
  13. Ghosts 2 glitches , is most awaited game for the gamer. Ghosts 2 offering so many things like: new weapons, maps, better graphics and more hiding spots. Call of Duty fans has an incredible eagerness towards Ghosts 2 though it’s not come yet.

    ReplyDelete