Life Phases Nutrition
The Importance of Protein
The word protein originates from the idea that proteins are central to life and the first nutrient. Vitamins – vita meaning life and amin meaning protein – got their name from the misconception that amino acids, the building blocks of protein, were the essential components for maintaining life.
Proteins are found in animals and plants, but the mixture of amino acids – the building blocks of the protein found from different sources – varies. As a result, there are 21 common amino acids consisting of 12 nonessential and nine essential amino acids. Essential amino acids are those that cannot be synthesized from other amino acids, but must be consumed in the diet. The usual way that nonessential amino acids are formed is by metabolism of other amino acids. All amino acids have a basic structure of an alpha-amino nitrogen and carboxylic acid.
Maintaining the amounts of protein in muscles and organs is essential to life and is the main objective of the adaptation to starvation. In fact, loss of more than 50 percent of body protein is incompatible with life. The protein is stored in organs and there is no labile compartment.
The Importance of Protein
There is evidence that modestly increasing the proportion of protein in the diet, while controlling total calorie intake, may:
* Improve body composition.
* Facilitate fat loss.
* Improve body weight maintenance after weight loss.
Fat Retention
Mankind is very well adapted to malnutrition and starvation, and this adaptation is reflected both in the way the body stores energy and how it uses these stores of energy when food intake is reduced or eliminated altogether. In the average 70 kg (154 lbs) man:
* The largest store of calories is in the form of fat in adipose tissue with approximately 135,000 calories* stored in 13.5 kg (30 lbs) of adipose tissue.
*A dietary calorie is 1,000 calories or a kcal, but for simplicity will simply be noted as calories. You may also see dietary calories capitalized as “Calories.”
This storage compartment can be greatly expanded with long-term overnutrition in obese individuals.
There are approximately 54,000 calories stored as protein both in muscle and organs, such as the heart and liver. Only half of these calories can be mobilized for energy, since depletion below 50 percent of total protein stores is incompatible with life. In addition to being an energy source, protein plays a functional role in many organs, including the liver, and depletion is associated with impaired immunity to infection. In fact, the most common cause of death in an epidemic of starvation is typically simple bacterial pneumonia. Conservation of protein is an adaptation tightly linked to survival during acute starvation.
Meal Replacement Shakes and Weight Maintenance
Studies show that meal replacement shakes are a viable way to maintain weight, as recognized by the European Food Safety Authority, and that increasing the protein to about 30 percent of resting metabolic rate, as estimated by bioelectrical impedance, leads to greater loss of fat with retention of lean body mass.
What about Antioxidants?
Antioxidants
Mankind evolved on Earth when it was already filled with plant life, and plants influenced human evolution. Plants interact with the atmosphere differently than humans. While humans consume oxygen and produce carbon dioxide, plants take in carbon dioxide from the air and produce oxygen. This oxygen produced by plants is a chemically reactive compound that would damage and kill the plant, so plants evolved the ability to make antioxidants such as Vitamin C, Vitamin E and colorful chemicals to protect their cells from the damaging effects of oxygen. This system sometimes breaks down and the damage from oxygen can be seen when a houseplant gets too little light or water and its leaves turn brown.
The oxygen we breathe can also damage human tissues, as illustrated by the damaging effects of 100 percent oxygen in intensive care units, where the lung tissue can be destroyed without proper protection. Like plants, humans evolved defense systems that are based on circulating substances and proteins. These systems are reinforced with the intake of antioxidants in the diet from colorful fruits and vegetables. There is overwhelming data showing that populations that consume a diet rich in colorful fruits and vegetables have lower risks of many common chronic diseases.
It takes very little to avoid vitamin and mineral deficiencies, but the optimal levels of intake of antioxidants are likely greater than the amounts needed to avoid deficiency.
Vitamin C
For example, humans, unlike many species of animals, have lost the gene for making Vitamin C, because it was part of ancient mankind’s diet, which was rich in Vitamin C from fruits and vegetables. Eating a single orange provides twice the recommended amount of Vitamin C needed to prevent Vitamin C deficiency. In the 1750s, sailors in the British navy developed the disease called scurvy, characterized by bleeding gums, corkscrew hairs and ultimately death, from a lack of Vitamin C. It was customary for sailors to eat no plants at sea. However, once it was discovered that eating limes or other citrus prevented scurvy, citrus became part of the sailors’ diets (which is why British sailors were called limeys).
Today, inadequate intake of antioxidants is not as noticeable as the deficiency disease of scurvy, but the inadequate intake of plants, including colorful fruits and vegetables, is thought to be associated with many chronic diseases of aging.
FREE Lifestyle Guide...
10 Secrets to Feel Great,
Burn Fat, and Live Longer
Just enter your details below
Your information is confidential
Weight Loss Challenge!
