→ Protein and muscles

A balanced diet: the potential renal acid load

Research has shown that a more acidic diet seems to decrease the mineral content of your bones. This is in particular of interest for people who are inactive and have a lower mineral bone density. This is also of importance for astronauts during their missions since astronaut bones already have less loading in space so they suffer from reduced bone mineral density.

One might think that the potential renal acid load derives from the acids in the food we eat. The main nutrients affecting the acid load of a diet are protein, calcium, potassium, phosphorus and magnesium. An algorithm to calculate the potential renal acid load (PRAL)  was developed by Remer & Manz (J Am Diet Assoc 1995). They took into account the absorption rates of nutrients in the gastrointestinal tract as well as the metabolic processes in the body

PRAL (mEq/d) = 0.49   * protein (g/d)

+ 0.037 * phosphorus (mg/d)

– 0.021  * potassium (mg/d)

– 0.026  * magnesium (mg/d)

– 0.013  * calcium (mg/d)

 

The information needed to calculate a PRAL  is often found on food packaging. Another way is to take information from tables of nutritional values. Precalculated PRALs are available such as www.saeure-basen-forum.de/pdf/IPEV-Food_table.pdf. To calculate the total PRAL of a meal you just add the food items together.

Food that is high in protein content, such as meat, fish, milk or cereals are acidic while vegetables and fruits are generally more alkaline because of their high potassium content. Meat lovers are highly recommended to combine meat with large portions of vegetables or fruits to compensate for the acidity from meat’s high protein content.

Martina Heer

Protein and muscles | ZeroG science lab

23/02/2015

Vegetable proteins: health served on a plate

Variation, variation and more variation: this is the correct way to ensure we eay all the nutrients that our body needs. For this reason the one dish meal helps us make every meal as complete as possible: 50% of your carbohydrate intake should come in fruits or vegetables, while 25% of your carbohydrate intake should come from whole grains and the last 25% should come from protein. As a condiment you can use extra-virgin olive oil. Proteins can be of animal or vegetable origin. To make your diet as varied as possible it is good to alternate animal proteins with vegetable ones. Meat, fish and eggs bring all the necessary amino acids to the body for its proper functioning. Since meat and eggs are also high in fat, it is good to alternate them with vegetable proteins from greens. Beans, lentils, chickpeas, peas and other vegetables, especially when dried, are important sources of protein as well as containing other properties such as a high fibre content. While it is true that plant proteins have a high biological value, but you can complement the intake of amino acids via the one dish meal scheme, accompanying  vegetables with whole-grain products that contain proteins. Let’s make greens a central component of our daily diet! Filippo Ongaro Read more: http://www.filippo-ongaro.it/

Not rocket science | Protein and muscles

03/02/2015

Animal protein: quality over quantity

In the second half of the 20th century the global consumption of meat increased fivefold, from 45 million tonnes consumed in 1950 to 250 million tonnes nowadays. The Food and Agriculture Organization estimates meat consumption is expected to double by 2050.

Today, in industrialized countries people consume an average of 224 g of meat per capita per day (over 81 kg per person per year) compared to an average of 30 g (almost 11 kg of meat a year per person) consumed in Africa.

Figures related to the animals slaughtered each year are exorbitant. 58 000 million chickens are slaughtered annually worldwide, 11 000 million in China and 9000 million in the United States alone. If you take other species into account, the numbers are still high: 1383 million pigs; 517 million sheep; 430 million goats; 296 million cows… In recent years, the consumption of meat has increased in China, India and most countries where a new middle class is emerging coupled with demographic growth.

Increased worldwide demand results in a massive growth of industrial production of meat and, therefore, concentration of power in the hands of a few large companies that can meet market demand. This transformation of the livestock sector and meat production has a long series of negative consequences on the environment, animal welfare, social equality as well as the health and quality of human life.

Everyone can contribute to improve the situation and change this trend however. For example you can: consume less meat; buy better quality; vary the species and races of animals you eat; choose different cuts; be wary of low prices; favour meat from locally-bred animals and avoid imported products as much as possible; learn to read product labels; consider animal welfare; ; be curious and ask your butcher for more information or visit a farm to see how animals are raised.

Finally remember that giving up some things often has an up-side: eating less meat is not a punishment, your health will benefit and so will the environment and animal welfare. “Replace” meat with tasty, seasonal food  and you will not even miss it!

Silvia Ceriani

For years, Slow Food is trying to raise awareness among consumers about eating better quality and less meat. This year, from 4 to 6 June, the international event Slow Meat will be held in Denver on this subject (https://www.slowfoodusa.org/slow-meat-2015), it is organised by Slow Food USA. To know more about Slow Food, click here: (http://www.slowfood.it/quanta-carne-mangiamo/).

It's rocket fuel | Protein and muscles

30/01/2015

Protein synthesis

The term protein synthesis refers to the biochemical process through which the genetic information in DNA is converted into proteins that perform biological functions in the body. A process called transcription froms a strand of messenger RNA from DNA  as a mold for the production of a protein. Protein synthesis is part of a complex series of metabolic reactions that, by consuming energy, form complex molecules from simpler ones to repair and rebuild damaged tissues. The opposite reactions that degrade complex molecules thereby releasing energy are called catabolic. Metabolism is characterized by a continuous succession of catabolic and anabolic reactions which vary depending on age, nutrition and environment . Because our bodies synthesis protein in a  regular and orderly manner it is necessary to provide the body with sufficient amounts of raw material, that is to say, dietary protein that will provide the necessary amino acids to turn into proteins. The amount of dietary protein varies according to the level of physical activity, and ranges from a minimum of 0.8 g per kg body weight for a sedentary person, up to 2 g for fit and powerful athletes. Furthermore, anabolic reactions are regulated by a number of hormones including insulin, growth hormone and testosterone which are influenced by food intake, type of physical activity and by the time between activity and recovery. During a long space mission it is essential to continue stimulating  protein synthesis to minimize catabolic reactions that load the muscle and bones. A balanced diet that ensures enough protein and a daily exercise program that offers intensive use of muscles with special tools to simulate weight training, logically impossible in orbit.

Dr. Filippo Ongaro

Read more: http://www.filippo-ongaro.it/

Not rocket science | Protein and muscles

29/01/2015

More “muscles”, more life

When it comes to muscles people often think of the sculpted bodies of athletes or bodybuilders.

But muscles are necessary to us all, just as the heart, brain, skin and bones, and we all have them. Few people know however, that after the age of 35, our muscle mass will decrease by  up to 1% each year. Once you reach the age of 75 years old if nothing is done to slow this process, you may find yourself with 40% less muscle mass! This muscle loss causes a loss of strength and autonomy that iss very often the basis of the downward spiral that leads to frailty of old-age that is marked by weakness, loss of balance and difficulty leaving home. In turn this can lead to psychological changes that lead to isolation and consequently even the slowing down of cognitive functions. Muscles health is not the only factor of course but remember that strong and healthy muscles help regulate glycaemia, blood pressure and even mood.  Muscles help keep strong bones and this is why they are a central aspect being in good health. There is no need to engage in extreme activities to avoid this downward spiral but make some  space in your weekly routine for some training with weights or resistance bands or a simple workout  coupled with a healthy dose of aerobic activity such as walking, running, swimming or cycling. Remember that to maintain  healthy muscles you need to absorb adequate protein by eating fish, vegetables and lean meats. If working out for cosmetic reasons is not your thing, before you dismiss exercise outright, remember that more muscle equals longer life. Dr. Filippo Ongaro to learn more: http://www.filippo-ongaro.it/ In the cover image: ESA astronaut Thomas Pesquet training on the Advanced Resistive Exercise Device at NASA Johnson Space Center’s Columbia Center, 16 September 2014.

Challenge | Protein and muscles

29/01/2015