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 Nanoparticle Exposure Can Awaken Dormant Viruses in the Lungs
16.01.2017 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Cholera bacteria infect more effectively with a simple twist of shape
13.01.2017 | Princeton University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

Im Focus: Newly proposed reference datasets improve weather satellite data quality

UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration

"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...

Im Focus: Repairing defects in fiber-reinforced plastics more efficiently

Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.

Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Multiregional brain on a chip

16.01.2017 | Power and Electrical Engineering

New technology enables 5-D imaging in live animals, humans

16.01.2017 | Information Technology

Researchers develop environmentally friendly soy air filter

16.01.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>