Masanori Tonegawa, Yomiuri Shimbun
The Spokesman Review
Sun, 28 Mar 2010 09:34 CDT
The Japan Society for Lipid Nutrition has drawn up new guidelines stating that high cholesterol levels are better for living longer, defying conventional wisdom.
There are two kinds of cholesterol - low-density lipoprotein (LDL) that is considered "bad," and high-density lipoprotein (HDL), which is regarded as "good" cholesterol. LDL cholesterol is delivered to cells throughout the body, while HDL is excess cholesterol collected from the body.
The Japan Atherosclerosis Society, an organization focusing on lifestyle-related diseases, has advocated people lower their LDL cholesterol levels by improving dietary habits and using medication, because high LDL levels could cause heart disease.
In 2007, the society set diagnostic criteria for hyperlipemia, or elevated levels of lipids in the bloodstream, flagging LDL cholesterol levels of at least 140 mg/dl and HDL levels less than 40 mg/dl as dangerous for both men and women.
"According to domestic and foreign research, the higher LDL levels become, the more arterial stiffening advances. Correspondingly, incidence of heart disease also rises. We concluded that LDL cholesterol levels more than 140 mg/dl could easily cause heart disease," said Hirotsugu Ueshima, professor emeritus at Shiga University of Medical Science, who devised the atherosclerosis society's criteria.
However, Tomohito Hamazaki, a professor at Toyama University's Institute of Natural Medicine, who compiled the new cholesterol levels guidelines for the Japan Society for Lipid Nutrition, countered Ueshima's argument. "When examining all causes of death, such as cancer, pneumonia and heart disease, the number of deaths attributable to LDL cholesterol levels exceeding 140 mg/dl is less than people with lower LDL cholesterol levels.