Cholesterol is often cited as a cause of cardiovascular disease and a low-fat diet is recommended as treatment and prevention for those at risk. But scientific research has been unable to prove that high dietary cholesterol intake increases blood cholesterol levels – in fact, there is now strong evidence to show that avoiding this kind of fat can actually have a negative affect on your health

Back in 1913 a Russian scientist, Dr Anitschkov, thought he had discovered the answer to heart disease: he found that it was induced by feeding cholesterol to rabbits. What he failed to realise was that rabbits, being vegetarians, have no means for dealing with this animal fat.
Since the fatty deposits in the arteries of people with heart disease have also been found to be high in cholesterol, it was soon thought that these deposits were the result of an excess of cholesterol in the blood, possibly caused by an excess of cholesterol in the diet.

Such a simple theory had its attractions and many doctors still advocate a low cholesterol diet as the answer to heart disease – despite a consistent lack of positive results. If the cholesterol theory were correct, we could expect that: people with high dietary cholesterol would have a high incidence of heart disease; raising dietary cholesterol would raise blood cholesterol; and blood cholesterol levels would be good predictors of heart disease.

Putting Cholesterol to the Test
Dr Alfin-Slater from the University of California decided to test the cholesterol theory1. “We, like everyone else, had been convinced that when you eat cholesterol you get cholesterol. When we stopped to think, none of the studies in the past had tested what happens to cholesterol levels when eggs, high in cholesterol, were added to a normal diet.”

He selected 50 healthy people with normal blood cholesterol levels. Half of them were given two eggs per day (in addition to the other cholesterol rich foods they were already eating as part of their normal diet) for eight weeks. The other half were given one extra egg per day for four weeks, then two extra eggs per day for the next four weeks. The results showed no change in blood cholesterol. Later, Dr Alfin-Slater commented “Our findings surprised us as much as ever...”

Three other studies 2,3,4 have also found no rise in blood cholesterol levels when extra eggs were added to people's diets. In fact, as long ago as 1974, a British advisory panel set up by the Government to look at 'medical aspects of food policy on diet related to cardiovascular disease' issued this statement: “Most of the dietary cholesterol in Western communities is derived from eggs, but we have found no evidence which relates the number of eggs consumed to heart disease.”5

During the height of cholesterol phobia, Dr Jolliffe, renowned for his weight-reducing diets, started an 'anti-coronary club' and placed 814 men, aged 40 to 59, all free from heart disease, on a low cholesterol, high polyunsaturated fat diet6. For a control group he had 463 men of similar age and health status, who continued with a normal, and thus relatively high cholesterol diet. Five years later, eight men on the low cholesterol diet had died from heart attacks, compared to none in the control group! Ironically, Dr Jolliffe himself died from vascular complications of diabetes at the age of 59, so he never lived to see the results.

The Inuit people of North America were always an enigma with regard to the cholesterol theory. Their traditional diet, high in seal meat, has among the highest cholesterol levels of any cultural diet, yet their rate of cardiovascular disease is among the lowest. Other foods rich in cholesterol include shrimps. A more recent study from Rockefeller University gave participants either three servings (300 grams) of shrimps or two large eggs a day, each providing 580mg of cholesterol. Researchers found that both groups had an increase in both the good HDL cholesterol and the less desirable LDL cholesterol (discussed over page), which they interpreted to mean that neither diet significantly altered cardiovascular risk. 7

It is now clear there is no strong relationship between intake of dietary cholesterol and cardiovascular disease. This said, however, a lot of high cholesterol foods also happen to be high in saturated fat and may be fried – and such foods are associated with an increased risk of cardiovascular disease. It is therefore prudent to not go overboard on high cholesterol foods, while at the same time, there is no need for cholesterol phobia.

A switch from animal protein towards vegetable protein, especially soya, does have significant effects on lowering blood cholesterol and fat levels, which is consistent with reducing risk. These beneficial effects occur with as little as a serving of tofu or two cups of soy milk a day.8

Good and Bad Cholesterol
We have now learnt that cholesterol itself isn't the bad guy. After all, the body actually makes cholesterol and we all carry about 150 grams (one-third of a pound) of it in our bodies. Of this, 7 grams is carried in our blood. The body needs cholesterol to make sex hormones, vitamin D and to digest and transport fats (lipids). Having said that, having a high blood cholesterol level is associated with doubling of the risk of cardiovascular disease. But it is the type of cholesterol in the body and the way the body clears excess from the arteries that makes cholesterol relevant.

Cholesterol is made in the liver and should return there after it has been released in bile into the digestive tract, where it helps digest fats before being reabsorbed into the bloodstream. Certain protein 'ships', known as low density lipoproteins (LDLs) have been found to be responsible for carrying cholesterol to the artery wall. While others, high density lipoproteins (HDLs), help to return cholesterol to the liver. So if you have a low LDL cholesterol count and a high HDL cholesterol count, that is good news because it would mean that most of your cholesterol was on the HDL 'ship' that could remove it from the arteries.

HDL cholesterol is sometimes thought of as 'good cholesterol' and LDL cholesterol as 'bad cholesterol'. Because of this, cholesterol tests now report not only your overall cholesterol level, but also how much of that cholesterol is on the good HDL ship, and how much on the bad LDL ship. If, for example, you have a high total cholesterol and much of it is in the form of LDL, your risk is high. While, if you have a low total cholesterol and much of it is on the HDL ship your risk is low. This is usually reported as the ratio of total cholesterol to HDL cholesterol. If it's 5:1 you have average risk, if its 8:1 you have a high risk and if its 3:1 you have a low risk.

Your Ideal Cholesterol Statistics
Most laboratories will report a 'normal' range for total blood cholesterol of 120 to 330mg%. While high cholesterol is considered a significant risk factor, low scores have, until recently been ignored. Yet increasing evidence is linking low cholesterol levels to a number of mental and physical health problems. Among these are hyperactive thyroid, certain cancers, suicidal and homicidal tendencies and mental illness. So there is a healthy balance – not too high, not too low.

Like blood sugar levels, so-called 'normal' cholesterol levels are based on people in average poor health. So what ranges exist in healthy people? This is the question

Dr Emmanuel Cheraskin and colleagues set out to answer in a study on 1,281 doctors, using an accepted health rating scale, called the Cornell Medical Index (CMI), in which the participants complete a questionnaire asking health-related questions. In the entire group, they found a range of cholesterol scores between 110 and 520mg%. The healthiest people, those with a score of 0 on the CMI had cholesterol levels between 176 and 239mg%. In another study on dental students, Cheraskin measured the effects of eliminating refined carbohydrates and comparing it with the health of their gums. Those who achieved the best dental rating after dietary changes had cholesterol scores in the narrow band of 190 to 210mg%. This can be considered an ideal cholesterol range.

Your ideal blood cholesterol levels

 

	Low Risk		Medium		High
	Mmol/l(UK)	Mg%  (US)	Mmol/l (UK)	Mg%  (US)	Mmol/l(UK)	Mg%  (US)
Cholesterol	<5.18	200	6.2	240	>6.7	260
HDLs	>0.91	35	0.7	27	<0.5	19.4
Cholesterol/HDLs	3:1		5:1		8:1

Improving Your Cholesterol Statistics With Niacin
One proven way to improve the cholesterol/HDL ratio, ie increasing the amount of the 'good' HDL form and lowering the LDL form, is to supplement niacin (vitamin B3). This is a highly effective strategy (which also helps to lower another risk factor, lipoprotein (a)) involving an inexpensive daily supplement. In one of the earlier studies on niacin, by Dr Grundy9, patients given niacin had a 22 per cent drop in total cholesterol and half the triglyceride level within a month! An appraisal of niacin in the Journal of the American Medication Association in 1986 concluded that it was “the first drug to be used” when dietary intervention had failed to correct cholesterol statistics.10

Since the 1980s two cholesterol lowering drugs, gemfribrozil and lovastatin, have gained popularity among doctors due to their cholesterol-lowering effects. Although this may be the case, they are not nearly as effective as niacin in raising the beneficial HDL levels, which is associated with a significant reduction in risk of cardiovascular disease. In fact, niacin is, on average, five times more effective in raising HDLs, according to three recent US studies11,12,13. Another study which combined niacin and gemfribrozil found that after four weeks total cholesterol and LDL had decreased by 14 per cent, HDL had increased by 24 per cent and the ratio of cholesterol to HDL had improved by 30 per cent14. That's enough to shift a person from the 'high risk' category to normal risk. What's more, blood fats – the triglycerides, fell by 52 per cent. These results are consistent with those of other studies on niacin so it is likely that much of this improvement was due to the niacin rather than the drug.

There is one problem, however. Niacin is a powerful vasodilator (ie it widens blood vessels) at the level needed to produce these results (500 to 1,500mg per day) and makes you blush for about 30 minutes. This effect is not harmful. In fact it's beneficial but many people do not like it and it certainly wouldn't be convenient to have this blushing reaction at work. By halving the dose, though, and taking it twice a day with food, the blushing usually lessens after a few days. An alternative is to take niacin inositolate, sometimes called 'no-flush niacin'. This is, however, not as effective in improving your cholesterol status and is best reserved for those who do not like the blushing effect of niacin.

Niacin has many positive effects on the cardiovascular system. Through its vasodilatory effect it improves circulation and may improve the elimination of excess cholesterol in this way. It also makes blood cells less sticky and therefore less likely to clump together, reducing the risk of a heart attack. It is certainly worth including in a prevention strategy for those with 'high risk' cholesterol figures.

The Dangers of Too Little Cholesterol
Since high blood cholesterol levels are associated with a high risk of coronary artery disease it is assumed that having a low cholesterol level is good news. Not so, according to three independent research groups. One in Japan found that, while high levels are associated with cardiovascular disease (the incidence of which is low in Japan) low levels are associated with incidence of strokes. As cholesterol levels dropped below 190mg%, in a group of 6,500 Japanese men, incidence of strokes increased. 15

Meanwhile, a Finnish researcher, Jykri Penttinen, has found a higher rate of depression, suicide and death from violent causes among those with very low cholesterol levels16. These findings were confirmed by David Freedman of the Centers for Disease Control in Atlanta who has found that people with antisocial personality disorders had lower cholesterol levels17. Freedman believes that people with very low cholesterol levels are more likely to be aggressive.

This suggests that cholesterol-lowering drugs should not be given to anyone unless their blood cholesterol level is high, even if they have cardiovascular disease.

How Healthy is Your Cholesterol?
Cholesterol is clearly an important substance in the body – dangers are associated with both too much and too little of it, and the form it is in (eg HDL or LDL). Another factor can also make it a potentially harmful substance. Being a fat-like substance, cholesterol can be oxidised, or damaged in the same way that oil paint is oxidised by the air when the lid is left off: it goes hard. As such, cholesterol can no longer be transported around the body in the normal way and there is increasing evidence that this may be an important factor in cardiovascular disease.

The next question is what damages cholesterol? The answer is oxidants, which arise from smoking, fried food, pollution and normal body processes, including over-exercising and anaerobic exercise. On the other side are the body's protectors, the antioxidant vitamins A, C and E plus minerals such as selenium and zinc. In truth there are hundreds of antioxidants in our food, especially in fresh fruit and vegetables. For example, in grapes you find proanthocyanadins, which is why a small amount of red wine may be mildly protective from heart disease, while too much alcohol is a well-known risk factor. Grape juice would be better. The antioxidant theory fits well with current research, which consistently shows a low risk of atherosclerosis among people with high intakes of anti-oxidant nutrients.

Beyond HDL and LDL Cholesterol
The HDL and LDL 'ships' are special compounds made of fat and protein, called a lipoprotein. Recently, scientists have started to study the levels of these individual lipoproteins to see whether this can help predict heart disease21. The lipoprotein that combines with cholesterol to produce the undesirable LDL cholesterol is called 'apoprotein B', or apo B for short. Having high levels of apo B both correlates with having high levels of LDL cholesterol and a higher risk of cardiovascular problems. The lipoprotein which combines with cholesterol to produce HDL cholesterol is called apoprotein A. (Actually there are two types: apo A1 and apo A2.) The higher your apoprotein A1 level the lower your risk.

More recent findings, however, are also suggesting that the 'problem' fat may in fact be a much more specific and different kind of lipoprotein, not just LDL or indeed damaged cholesterol. Investigations into the fat deposits blocking vessels in people who had died from cardiovascular disease found a very high level of something called apoprotein (a) (not to be confused with apoprotein A), which the body makes under certain circumstances. Apoprotein (a) has a natural affinity for attracting lipids, binding with them to become lipoprotein (a), which readily sticks to artery walls.  Levels of lipoprotein (a) are therefore highly predictive of cardiovascular disease, which presents a remarkable new theory on a major underlying cause and treatment of cardiovascular disease.

Which eggs are best?
Although eggs have been unfairly maligned as high in fat and cholesterol, they can be good for the brain and the heart. But not all eggs are created equal – the nutritional quality is determined by the diet of the hen. Battery chickens are often fed a high animal protein diet to promote growth, which also contains high levels of saturated fat. The fat in their eggs is therefore predominantly saturated. On the other hand, a free-range chicken is often fed grains, high in unsaturated fats, making their eggs high in these too.

Columbus free-range eggs, now sold in most supermarkets, are high in omega 3 fats. That's because the chickens are fed seeds naturally rich in this highly beneficial fat which not only protects against heart disease, but is positively good for the brain. Higher levels of omega 3s not only equate with higher IQs in children, but also improved memory in adults. But that's not all.

The key brain chemical for memory is acetylcholine, deficiency of which is probably the single most common cause for declining memory. The main dietary source of choline is eggs. Choline not only makes the memory molecule acetylcholine, it is also a vital part of the brain's structure. Recent research at Duke University Medical Center has shown that giving choline during pregnancy creates the equivalent of superbrains in the offspring, with improved learning ability and better memory recall, all of which persisted into old age. This research showed that eating choline-rich food helps restructure the brain for improved performance.

So, eggs are not only a good source of protein, but also – if you buy free-range – a valuable provider of essential fats and brain nutrients. But to keep the nutrients intact and limit damage during cooking, boil rather than fry your egg.

References
1 Reported at the International Congress of Nutrition in Kyoto, Japan 1975 by Dr. R. Alfin-Slater
2 Passwater R. Supernutrition for a Healthy Heart.  Thorsons Publishing Limited. 1977.p. 67. 
3 Hirshowitz B et al. 35 Eggs Per Day in the Treatment of Severe Burns. Br J Plast Surg 1975;28(3):185-188
4 Herbert P. Medical World News February 1977.
5 Report of the Advisory Panel  of the Committee on Medical Aspects of Food Policy on Diet in Relation to Cardiovascular and Cerebrovascular Disease. Diet and Coronary Heart Disease, London:1974.
6 Jolliffe
7 De Oliviera e Silva et al. Am J Clin Nutr 1996;64(5):712-7
8 Russell, R. Soy Protein and nutrition. JAMA 1997:277(23):1876-1878
9 Grundy S et al. Influence of nicotinic acid on metabolism of cholesterol and triglycerides in man. J. Lipid Res. 22:24-36, 1981
10 Hoeg J et al. Special communication: an approach to the management of hyperlipoproteinemia. Metabolism 34(11):1073-7,1985
11 O'Connor P, Rush W et al. Relative effectiveness of niacin and lovastatin for treatment of dyslipidemias in a health maintenance organization. J. Fam Pract 1997 May; 44(5):462-467
12 Illingworth D, Stein E et al. Comparative effects of lovastatin and niacin in primary hypercholesterolemia. A prospective trial. Arch Intern Med July 25 1994;154(14):1586-1595
13 Gardner S, Schneider E et al. combination therapy with low-dose lovastatin and niacin is as effective as higher dose lovastatin. Pharmacotherapy May 1996;16(3):419-423
14 Vega G, Grundy S. Lipoprotein responses to treatment with lovastatin, gemfibrozil and nicotinic acid in normolipidemic patients with hypoalphalipoprotein. Arch Intern Med 1994 Jan 10;154(1):73-82
15 Ueshima H et al.Prevent Med 1979; 8:1:104-105
16 New Scientist, 29 April, 1995:10
17 Ref to David Freedman, Centers for Disease Control, in Optimum Nutrition 1995;8(2):8-9