Triglyceride – The Neglected Fat

This article is Part 2 of my earlier  article “What is Cholesterol- The Good and the Bad”

While people are aware of Cholesterol and know that it can be harmful if present  in excess in the blood, few know about Triglycerides and their potentially harmful effects.

For a long time the role of triglycerides in the causation of heart disease was uncertain. Their nature and function is now better understood.

When the doctor measures your cholesterol, he also asks for a Triglyceride level.

What are Triglycerides

Triglycerides are a type of Fat, formed from one molecule of Glycerol, combined with three Fatty Acids. They come from the food we eat as well as being produced in the body. See my Article– What is all the Fuss about Fats”

The Fatty Acids can be either saturated, mono-unsaturated or poly unsaturated.

Saturated fatty acids typically occur in fats of animal origin, including dairy foods and fat in meat.  

monounsaturated fatty acids occur in plant fats, such as , Olive and Canola oil, and nuts such as macadamia.

polyunsaturated fatty acids are of two main types: omega-3’s, which occur in fish oils  and omega-6’s which are present in plant

oils such as  safflower and sunflower seeds

The type and proportion of fatty acids determines  the physical properties and appearance of the the triglyceride . For example cheese and butter are solid at room temperature while olive oil, safflower and canola are usually liquid.

When we ingest Fat in our diet, the digestive process called lipolysis breaks down the triglycerides into glycerol and fatty acids which are transported to the small intestine. In the wall of the small intestine there are cells called enterocytes. The fatty acids are absorbed into these cells and  they are re-formed into triglycerides and combined with cholesterol (VLDL) and proteins into particles called chylomicrons . These chylomicrons are excreted  from the cells, collected and transported via the Lymphatic System before they enter the blood stream via the large vessels near the heart. They are then used by various tissues for energy or taken up by fat cells for storage.

The Function of Triglycerides

The fat tissue under the skin of animals, birds and fish is mainly made of triglyceride and is essential for life ; it is

– part of the heat regulating system. It insulates the body against heat loss

– provides energy for metabolism and various bodily functions.                                              

Whaling is a very topical subject at the moment in the world-wide press. In the 1800’s, the whalers were very aware  of the importance and value of the fat under the skin of whales. This ” blubber”, which is mainly made of triglycerides, serves to insulate the whale against the cold and provide energy for its metabolism.

Blubber was melted down and transported in barrels to Europe where it provided the oil for lighting and heating for many years.

How is Triglyceride Measured

In humans it is possible to find the type and measure of fats ingested in the everyday diet by taking a biopsy of the sub-cutaneous fat and analyzing its fatty acid content.

Normally your Doctor will check your blood triglyceride level, when checking your Cholesterol. This is done after an over-night fast   ( ideally at least 12 hours ) . This is necessary for consistency in testing , because soon after a meal the blood triglyceride level will be high due to absorption from fatty food. The level will remain high for several hours.

Because, Alcohol, certain medications and over-the- counter products and supplements may affect your Triglyceride level, it is important to make certain that your Doctor knows exactly what you are taking.  It may be necessary to stop these for a short period prior to a test. But remember NEVER stop taking prescribed medication unless advised to do so by your Doctor.

Drugs that can increase triglyceride measurements include beta blockers, cholestyramine, oestrogens, protease inhibitors, retinoids, certain anti psychotics, and birth control pills.

Drugs that can decrease triglyceride measurements include Vitamin C (ascorbic acid), asparaginase, clofibrate, fenofibrate, fish oil, gemfibrozil, nicotinic acid, and statin medications.

The National Heart Foundation of Australia make the following recommendations:

The suggested target levels for blood cholesterol are:
– LDL-cholesterol <2.0 mmol/L
– HDL-cholesterol > 1.2 mmol/L
– Triglycerides <1.5 mmol/L

in the absence of any other risk factors. If other diseases are present the recommendation is for an even lower level

Why should we be concerned about Triglycerides.

Triglycerides play an important role in diseases such as Obesity, Diabetes and Heart Disease.

The metabolism of Triglycerides(TG) is intimately linked to that of Cholesterol, both LDL and HDL.  Changes in Triglyceride levels can  affect LDL (bad cholesterol) and HDL  levels. This is especially so in relation to HDL – the “good cholesterol”.  When there is a rise in triglyceride there tends to a fall in HDL which is not good . When TG is low the HDL tends to be high  – this is good.  Therefore it is important for the Doctor to consider each of these fats together. For a long time this was not the case and triglycerides were the ” forgotten fats”.

  • A raised TG can have an effect on certain clotting factors in the blood. This can increase the tendency for thrombosis to occur and an increase in the risk of heart attack.
  • There are Familial diseases in which TG and Cholesterol are raised. These result in heart disease at an early age.
  • Under-active thyroid disease (hypothyroidism ) can result in obesity, elevated Lipids  and heart disease
  • Raised Triglycerides may be one of the first signs of Diabetes.

I would recommend that you look at my article on Cholesterol, for a more details regarding HDL and LDL

There are many excellent books available on the subject discussed and related topics at—–

Premiere

 

Also check out Dr Al Sears excellent Krill Oil product, Ultra-omegano”  and the section, “Heart Health” by clicking on this Link – “ Can Your Stinky Fish Oil Do This? ‘

Conclusion

We have seen that  ‘Triglyceride – The Neglected Fat’, has an important role in the causation of Heart Disease and Diabetes particularly but, is also implicated in other potentially serious medical conditions.

In my next article I will deal with some of the important Solutions to the problem of Hyper-triglyceridaemia and how we can bring about change.

Doctor  Bill

What is all the Fuss about Fats

The Facts about Fats

As we discovered when discussing Carbohyrates , there are many misconceptions about their role in our diet. This is even more so when we talk about FATS . The food industry has done much to foster the belief that Fats are bad by their emphasis on Low fat or No fat foods. While the low fat approach to eating  has helped some individuals, as a nation it has not helped us control weight or become healthier. The incidence of  Obesity is increasing at an alarming rate, especially in children. As a consequence, the incidence of  Diabetes is also increasing dramatically.

So what is the answer to this problem? To answer that question, again,we must understand the Facts about Fats

  • What are Fats ?
  • What is the function of Fats in our body ?
  • Classification and sources of Fats.
  • What is the optimum amount of Fat in our diet ?

What are  Fats ?

Fats usually describe a wide range of substances that  generally will dissolve in organic solvents, but are largely insoluble  in water. There are many other terms used to describe fats namely lipids,triglycerides, oils and waxes. The term “Fat” is usually used to refer to fats that are solid at room  temperature, while “oils” refers to those that are liquid at room temperature. “Lipids”, is used to refer to both solid and liquid fats , along with other related substances. There are many different kinds of fats, each being a variation on the same chemical structure. All fats consist of  fatty acids.  Natural fats , whether they are derived from animal or plant sources are composed of three fatty acid molecules (that’s the “tri” in triglycerides) bound to one glycerol (a type of alcohol ) molecule. The properties of any specific fat molecule depends on the particular fatty acids of which it is composed. There are about 25 different fatty acids that can be attached to the glycerol backbone structure.

Function of Fats in our Body

Fats are important  for many body processes. Almost all foods contain some fat. Even so called fat free foods such as carrots and lettuce contain small amounts of this nutrient. You need to eat some fat in your diet. Even if the diet contains no fat, the body will convert excess protein and carbohydrate to fat and store them as such. Fats play a vital role in maintaining healthy skin and hair. Fat protects and insulates  body organs against shock, keeps you warm and helps maintain body temperature. It  helps your body absorb and move nutrients around;  eg the fat soluble vitamins A,D,E and K.  It also helps hormone production. Fat also serves as a useful buffer against many diseases. When a substance reaches unsafe levels in the blood stream, the body can store the offending substance in new fat tissue. This helps protect vital organs until such time as the offending  substances can be metabolised and/or removed from the body. While it is nearly impossible to remove fat completely from the diet, it would be unhealthy to do so. Some fatty acids are essential nutrients for numerous chemical processes.  They cannot be produced in the body from other compounds and need to be consumed in small amounts ( See 3a & 3b below).  The two essential fatty acids are linoleic and alpha- linoleic acid All other fats required by the body are non-essential and can be produced in the body from other compounds.

Classification and source of Fats

Dietary fats are classified by their  structure. Different types of fats react differently in the body. Dietary fat can be classified into four main  groups:

1.  Saturated Fats
2.  Mono-unsaturated Fats
3.  Poly-unsaturated Fats can be divided into 2 categories.                                                                                   (a) Omega -3 fats        (b)  Omega-6  fats
4.  Trans Fats

1. Saturated Fats are fats that are solid at room temperature and come mainly from animal food sources, including meat and dairy products. Examples are fatty beef, lamb, pork, poultry with skin, beef fat (Tallow), lard and cream, butter, cheese and other dairy products made from whole or reduced-fat milk.
In addition, many baked goods and fried foods can contain high levels of saturated fats.  Some plant foods, such as palm oil, palm kernel oil and coconut oil, also contain primarily saturated fats, but do not contain cholesterol. These foods also contain dietary Cholesterol. Increased blood cholesterol is an important risk factor in coronary heart disease.

2. Mono-unsaturated Fats are typically liquid at room temperature but start to turn solid when chilled.  Olive oil, canola and peanut oils are good  examples. They are also found in avocado and nuts such as peanuts, hazelnuts, cashews and almonds. One of their beneficial effects is to lower LDL-cholesterol levels.

3. Poly-unsaturated Fats can be found mostly in grain products, fish and sea food, vegetable oils such as safflower,corn or Soy oils, nuts such as walnuts and brazil nuts and seeds. Foods like mayonnaise and soft margarine may also be good sources, but nutritional factors can vary by style and brand.

( a ) Omega-3 Fats are found in both plant and marine foods. Plant food sources include linseed, walnuts, canola and soy oils and canola based margarine. It is the omega-3 from fish, fish oil and seafood, that has the strongest evidence for health benefits, including reducing the risk of heart disease. Oily fish such as Atlantic salmon, mackerel, herring, Southern blue fin tuna , trevally and sardines have a high omega-3 content. There has been some evidence suggesting omega-3 fatty acids can reduce prostate tumour growth, reduce the tendency to blood clotting, lower triglyceride levels, reduce inflammation and support the immune system.

( b ) Omega-6 Fats are found primarily in foods that come from plant sources such as nuts, seeds and plant oils such as corn, soy, sunflower and safflower. These may also reduce the risk of cardiovascular disease. The omega-3 fats provide the essential fatty acid alpha-linoleic acid, while the omega-6 fats provide linoleic acid

4. Trans Fats are rare in nature. They are only created in the rumen of cows and sheep and are found naturally in small amounts in milk, cheese, beef and lamb
Commonly they are  fats created when a vegetable oil undergoes a process called  hydrogenation. The liquid vegetable oil is heated in the presence of hydrogen gas.  The process is used to make liquids more solid and to improve the stability and extend shelf life  of processed foods . This occurs in the manufacture of some table margarines  and in solid spreads used in the food industry to make baked products such as pies , pastries, cakes biscuits and buns. Fully hydrogenating a vegetable oil creates a fat that acts like a saturated fat. Trans fats are far worse than saturated fats when it comes to heart disease.

What is the optimum amount of Fat in our Diet ?

  • As we have seen, almost all foods contain some fat. Most experts recommend that adults restrict their fat intake to no more than 30% of each day’s Kilojoules. Some authorities say this should be lower, with10-25% frpm mono-unsaturated fats and  8 -10%  from poly-unsaturated fats.
  • Research has shown that the total amount of fat in the diet isn’t really linked to obesity or disease. What really matters is the type of fat in the diet. Since no one eats by percentage of daily kilojoules (or calories ), a good rule of thumb  is to choose unsaturated fats instead of saturated as far as possible.
  • Bad fats – saturated and trans fats – increase the risk for developing certain diseases, while Good fats, mono-unsaturated and poly unsaturated fats, can have a positive effect on the heart and other parts of the body .
  • Researchers have found that people who have a high intake of mono-unsaturated fats from olive oil, ( for example, those from Mediterranean countries such as Greece and Italy),  tend to have a low incidence of coronary artery disease, regardless of their body weight. The other important factor in the diet of people from these regions is the high intake of vegetables, legumes, fruits and cereals which are also rich in antioxidants

The Take Home Message when discussing Fats is – Look for foods with the least amount of saturated fat and a good mixture of unsaturated fat especially those containing the essential fatty acids.

 

In my next article I will talk about the relationship of Fats and Cholesterol

Doctor Bill.

Acknowledgements:  en.wikipedia.org/wiki/Fat
Harvard School of Public Health