Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Danish researchers finally solve the obesity riddle

25.11.2010
Researchers at the Faculty of Life Sciences (LIFE), University of Copenhagen, can now unveil the results of the world's largest diet study: If you want to lose weight, you should maintain a diet that is high in proteins with more lean meat, low-fat dairy products and beans and fewer finely refined starch calories such as white bread and white rice.

With this diet, you can also eat until you are full without counting calories and without gaining weight. Finally, the extensive study concludes that the official dietary recommendations are not sufficient for preventing obesity.

The large-scale random study called Diogenes has investigated the optimum diet composition for preventing and treating obesity. The study was conducted by eight European research centres and headed by Thomas Meinert Larsen, PhD, and Professor Arne Astrup, DrMedSc and Head of Department at the Faculty of Life Sciences (LIFE) and is funded by an EU grant of EUR 14.5 million.

The results were recently published in the distinguished New England Journal of Medicine and have already attracted considerable international attention.

The objective of the Diogenes study has been to compare the official dietary recommendations in Europe, including the Danish recommendations, with a diet based on the latest knowledge about the importance of proteins and carbohydrates for appetite regulation. A total of 772 European families participated, comprising 938 adult family members and 827 children. The overweight adults initially followed an 800 kcal/day diet for eight weeks, losing an average of 11 kg. They were then randomly assigned to one of five different low-fat diet types which they followed for six months in order to test which diet was most effective at preventing weight regain. Throughout the project, the families received expert guidance from dieticians and were asked to provide blood and urine samples.

The five diet types

The design comprised the following five diet types:

A low-protein diet (13% of energy consumed) with a high glycemic index (GI)*
A low-protein, low-GI diet
A high-protein (25% of energy consumed), low-GI diet
A high-protein, high-GI diet
A control group which followed the current dietary recommendations without special instructions regarding glycemic index levels

A high-protein, low-GI diet works best

A total of 938 overweight adults with a mean body mass index (BMI) of 34 kg/sq m were initially placed on an 800-kcal-per-day diet for eight weeks before the actual diet intervention was initiated. A total of 773 adult participants completed this initial weight-loss phase and were then randomly assigned to one of five different diet types, where 548 participants completed the six-month diet intervention (completion rate of 71%).

Fewer participants in the high-protein, low-GI groups dropped out of the project than in the low-protein, high-GI group (26.4% and 25.6%, respectively, vs. 37.4%; P = 0.02 and P = 0.01 for the two comparisons, respectively). The initial weight loss on the 800-kcal diet was an average of 11.0 kg.

The average weight regain among all participants was 0.5 kg, but among the participants who completed the study, those in the low-protein/high-GI group showed the poorest results with a significant weight gain of 1.67 kg. The weight regain was 0.93 kg less for participants on a high-protein diet than for those on a low-protein diet and 0.95 kg less in the groups on a low-GI diet compared to those on a high-GI diet.

The children's study

The results of the children's study have been published in a separate article in the American medical journal Pediatrics. In the families, there were 827 children who only participated in the diet intervention. Thus, they were never required to go on a diet or count calories – they simply followed the same diet as their parents. Approx. 45% of the children in these families were overweight. The results of the children's study were remarkable: In the group of children who maintained a high-protein, low-GI diet the prevalence of overweight dropped spontaneously from approx. 46% to 39% – a decrease of approx. 15%.

Proteins and low-GI foods ad libitum – the way ahead

The Diogenes study shows that the current dietary recommendations are not optimal for preventing weight gain among overweight people. A diet consisting of a slightly higher protein content and low-GI foods ad libitum appears to be easier to observe and has been documented to ensure that overweight people who have lost weight maintain their weight loss. Furthermore, the diet results in a spontaneous drop in the prevalence of overweight among their children.

*Re. Glycemic index, please see the accompanying appendix

References:

1. "Diets with High or Low Protein Content and Glycemic Index for Weight-Loss Maintenance" Thomas Meinert Larsen, PhD, Stine-Mathilde Dalskov, MSc, Marleen van Baak, PhD, Susan Ann Jebb, PhD, Angeliki Papadaki, PhD, Andreas F.H. Pfeiffer, MD, J. Alfredo Martinez, PhD, Teodora Handjieva-Darlenska, MD, PhD, Marie Kunešová, MD, PhD, Mats Pihlsgård, PhD, Steen Stender, MD, PhD, Claus Holst, PhD, Wim H.M. Saris, MD, PhD, and Arne Astrup, MD, DrMedSc, for the Diet, Obesity, and Genes (Diogenes) Project; New England Journal of Medicine, published online 25 Nov. 2010.

2. The Effect of Protein and Glycemic Index on Children's Body Composition: The DiOGenes Randomized Study; Angeliki Papadaki Manolis Linardakis, Thomas M. Larsen, Marleen A. van Baak, Anna Karin Lindroos, Andreas F. H. Pfeiffer, J. Alfredo Martinez, Teodora, Handjieva-Darlenska, Marie Kunesová, Claus Holst, Arne Astrup, Wim H. M. Saris and Anthony Kafatos on behalf of the Diogenes Study Group; Pediatrics, Vol. 126, 5 Nov. 2010.

For more information, please contact:

Professor Arne Astrup, DrMedSc, Head of the pan-European diet intervention study Diogenes
Email: ast@life.ku.dk
Tel.: +45 2143 3302
Associate Professor Thomas Meinert Larsen, PhD, Head of Project and Principal Author of the NEJM article
Email: tml@life.ku.dk
Tel.: +45 2271 7058
* Eat more proteins and less refined starch (low GI)
The glycemic index is a measure of the ability of carbohydrates to increase blood glucose levels when absorbed in the body. Food with a low-glycemic index (LGI) causes blood glucose levels to increase more slowly and to lower levels compared to high-carbohydrate foods with a high glycemic index

Drastic increases in blood glucose levels give rise to several potentially undesirable effects that can influence the body's metabolism as well as our ability to perform mentally. It is therefore most appropriate to maintain a diet that results in slow digestion and thus more stable blood glucose levels and greater satiety.

A diet with a high protein content contains many protein-rich foods such as lean meat, poultry, fish, eggs and low-fat dairy products. Legumes also contain high levels of protein, as do nuts and almonds. Proteins are significantly more filling than both carbohydrates and fat.

Special requirements for a low-glycemic diet

The glycemic index applies to carbohydrate-containing foods. The recommendations are that some types of fruit may be consumed ad libitum, such as apples, pears, oranges, raspberries and strawberries. Other types should be eaten in only very limited amounts, including bananas (especially overripe bananas), grapes, kiwi, pineapple and melon. Nearly all vegetables are permitted, with the exception of corn, which should be limited. Carrots, beets and parsnip should preferably be eaten raw.

With regard to cereal-based foods (bread, grain, corn, hulled grains and breakfast products), the goal is to eat as many coarse and wholegrain foods as possible, i.e. wholegrain breads with many kernels, wholegrain pasta, whole oats and the special varieties of wholegrain cornflakes

Potatoes should be cooked as little as possible. Try to stick to new potatoes, and it is a good idea to eat them cold. Avoid mashed potatoes and baked potatoes.

Pasta should be cooked al dente and is best eaten cold.

Choose rice varieties such as brown rice, parboiled rice or basmati.

White bread without kernels, white rice and sugary breakfast products should be avoided. In general, sugar intake should be limited, not so much because of its GI but to avoid all those 'empty calories'.

Recommended GI values:

Over 70 – high GI
55-70 – medium GI
Under 55 – low GI
High-GI foods can still be healthy and vice versa. Carrots, for instance, have a high GI (72), while chocolate has a low GI (49). Fats help decrease the absorption of sugar in the blood, which means that carbohydrate-containing foods and fat can have a low GI.

Example of a day's menu for a high-protein, low-GI diet

If you want to maintain a high-protein, low-GI diet, daily meals could be composed as follows:

Breakfast: Low-fat A38 with muesli (without added sugar), wholegrain crispbread with low-fat cheese, an orange

Morning: Vegetable sticks and low-fat cheese sticks

Lunch: Wholegrain rye bread with lean meat or chicken cold cuts, mackerel in tomato sauce and misc. vegetables

Afternoon: Wholegrain rye bread with low-fat liver pâté and cucumber

Dinner: Stir-fried turkey with vegetables and wholegrain pasta; avocado salad with feta cheese and sugar peas

It is best to drink water or low-fat milk with meals.

To sum up, there is nothing particular about this diet with the exception of the above-mentioned limitations, special cooking instructions and the fact that certain vegetables should be eaten raw. This diet generally complies with the official dietary recommendations of eating plenty of fruit and vegetables, low-fat foods, plenty of fibre and limiting sugar intake.

Professor Arne Astrup | EurekAlert!
Further information:
http://www.ku.dk

More articles from Life Sciences:

nachricht World’s Largest Study on Allergic Rhinitis Reveals new Risk Genes
17.07.2018 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Plant mothers talk to their embryos via the hormone auxin
17.07.2018 | Institute of Science and Technology Austria

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

World’s Largest Study on Allergic Rhinitis Reveals new Risk Genes

17.07.2018 | Life Sciences

Electronic stickers to streamline large-scale 'internet of things'

17.07.2018 | Information Technology

Behavior-influencing policies are critical for mass market success of low carbon vehicles

17.07.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>