WHAT’S IN FOOD?

Internal wellness begins with what we put into our bodies to fuel them.  It is essential to have an understanding of what our food consists of and why certain foods are better than others.

Consider our food as grouped into carbohydrates, fats and protein, vitamins, minerals, fibre and water (all classified due to their molecular structures), and what these do in the body.

Carbohydrates are essential to provide glucose to the brain and nervous system. The body will convert protein to carbohydrates when carb stores are low. (i.e. when less that 100 to 150 g/day are consumed. This is known as ketosis. Carbohydrates are also used as the primary fuel for muscles in the first 20 minutes of exercise and to maintain metabolic processes including the breakdown of free fatty acids. They have 2 basic forms

1. Complex (such as fruits, vegetables and whole grains).  They have slower and longer effects on blood sugar levels to allow the body to use them for energy for longer periods.  They are great sources of fibre, minerals and vitamins.
2. Refined (such as soft drinks, lollies, chocolate and white bread).  They have many calories with minimal nutritional value.  They raise the blood sugar quickly making you feel great but then drop quickly to provide a hypoglycaemic effect of tiredness, dizziness, irritability and decreased mood.  It is refined carbs that create carb addictions with withdrawal symptoms leading to cravings for more refined carbs.  It’s also these that lead to insulin resistance.

Carbohydrates are rated on the way they raise blood glucose levels in the body. This is        known as the glycaemic index.

Fats are energy storage molecules and contain vitamin A, D, E and K. They are used in exercise of longer than 20 minute duration at medium intensity. There are 3 basic forms

1. Simple fats (triglycerides) have 2 groups

• Saturated fatty acids (from animal fats such as meat, egg yolks, dairy and shell fish) and
• Unsaturated (from plants such as corn, olive, sunflower and peanuts)

1. Compound fats are simple fats combined with other chemicals such as phospholipids(seen in cell membranes) and lipoproteins(transport molecules in the blood).  The lipoproteins are important as they are commonly tested on lipid/cholesterol tests that GPs perform.  Lipoproteins are of 3 classes; high density (HDL), low density (LDL) and very low density (VLDL). The HDLs are the good lipoproteins that take cholesterol away from blood vessel walls to the liver where they are broken down by bile and excreted into the intestines.  Exercise can increase HDL’s.  LDL’s are ‘bad’ lipoproteins  as they carry cholesterol through the body allowing it to deposit in arteries.  
2. Derived fats are combinations of simple and compound fats eg. Cholesterol.  Not all cholesterol is bad as the body does need some cholesterol to make sex hormones and vitamin D. Its having too much that makes its dangerous.

Proteins are the third nutrient and are arguably the most important. They comprise of amino acids (i.e. the building blocks of nature.  They make hormones and enzymes, maintain water and acid balance, carry oxygen in the blood, maintain growth and repair cells/tissue. and provide 10 to 15% of total energy in prolonged exercise.  Proteins constitute 50% of dry body weight. There are 2 types – essential and non-essential.  Essential amino acids cannot be made by the body and must be ingested while non-essential ones can be synthesized from essential amino acids. They must be in correct amounts in the body to allow the body to function.  They are derived from animal products.  Some grains and beans have proteins but usually lack one or more essential amino acids.

Vitamins allow fats, carbohydrates and proteins to release energy essential for the formation of red blood cells, connective tissue and DNA production. Deficiencies cause the body’s biochemical processes to fail causing diseases. Some vitamins are strong anti-oxidants that bind dangerous free radicals that move around the body damaging tissues. There are 2 types of vitamins

1. Water soluble include vitamins C, B1, B2, B6, B12, folic acid, panthanoic acid and biotin. Deficiencies can occur within only 2 – 4 weeks, but excesses are eliminated in urine.
2. Fat soluble include vitamins A, D, E and K. Deficiencies are rare but becoming more common while excesses of A and D can cause be toxic to the body.

Minerals are enzymes or co-enzymes aiding in cellular and energy metabolism, allow muscle and nerve conduction and act to maintain the acid/base balance in body fluids. They are also used in teeth, bone, haemoglobin, protein and hormone synthesis. There are 6 major minerals; calcium, phosphorous, magnesium, potassium, sodium and chloride. The body requires in excess of 100mg per day of these minerals per day. Trace minerals need less that 100mg per day. There are 14 of these in the body; chromium, cobalt, copper, fluoride, iodine, iron, manganese, molybdenum, nickel, selenium, silicon, tin, vanadium and zinc.

Fibre provides bulk to stools to remove toxins, soak up fats, reduce appetite, and reduce the risk of colon cancers. There are two types of fibre. Water soluble fibre (beans and oats) acts to bind fats to reduce cholesterol, while water insoluble fibre (wheat) adds bulk. The body needs 25 to 40 grams of insoluble/soluble fibre is every day.

Water is essential for life. Two-thirds of the body’s composition is water as is 85% of the brain. Water is essential for digestion, absorption, circulation and excretion. It regulates body temperature, lubricates joints, moisturizes skin and maintains muscle. The body requires 8 to 10 glasses daily.

Just a note on vitamin and mineral supplementation

There is much controversy regards supplementation being a waste of money. This would be true if we ate fresh food from the garden which had no pesticide exposure and a high soil nutrient content.  Nowadays, this is an unlikely situation and so for efficient body functions to occur supplementation is essential.  However, many of the over the counter preparations consist of low doses with low grade ingredients.  The result is that you need more to get the desired effect.  So when choosing supplements select only high grade, concentrated products. These will be cost effective.  Your anti-aging doctor should be aware of these and can make recommendations.  Ask what they use for themselves and their families!

The glycaemic index (GI) is a rating of carbohydrate foods from 0 to 100 indicating how these foods raise blood glucose levels in the body when eaten. This is important when dealing with insulin resistance and diabetes as those foods with lower GI require less insulin to control blood glucose rises.

The GI rating is not the only factor in choosing suitable carbohydrates in a diet. Generally the slower the digestion the better the glycaemic control as well as appetite control. Factors that slow digestion of carbohydrates include

1. the type of starch
2. increasing particle size
3. choosing less ripe fruit
4. less cooking and processing of food
5. water soluble fibre
6. the type of sugar chosen, eg; fruit sugars digest slower that sucrose
7. adding fat and protein
8. increasing the acidity eg; adding lemon or vinegar

The amount of carbohydrate is equally important as the type.  This is indicated by the glycaemic load calculated as

The ideal GI food is high in fibre and low in fat.

A point of importance in reference to diets is the use of the word ‘diet’ itself.  To many this word implies temporary eating changes to produce a desired effect, usually weight loss.  I prefer to use the word ‘lifestyle eating plans’, as it is only long term changes that will provide satisfactorily lasting results.  The word diet in this context simply means an eating plan.

All anti-aging diets, i.e. lifestyle eating plans, should be tailored to the individual.  However some basic rules can be applied.

They should be balanced with

Calorie intake should be around 1800/day for the average 70kg moderately active person.

This balance will change depending upon exercise, insulin resistance and maximizing the use of growth hormone.