Friday, May 05, 2006

Eggs and your heart - dispelling the myth

Ingestion of several eggs a day tends to increase blood concentrations of cholesterol, particularly the amount circulating in low-density lipoproteins (LDLs)—the so-called bad cholesterol. However, a new study indicates eating eggs can increase the amount of cholesterol in high-density lipoproteins (HDLs)—the good cholesterol, too.

The study also showed that when people ate three or more eggs per day their bodies made bigger LDL- and HDL-lipoprotein particles than when they ate no eggs. That's important because other recent studies have suggested that larger LDLs are less likely than small ones to enter artery walls and contribute their cholesterol load to artery-clogging plaque. Similarly, larger HDLs are more robust than smaller ones at hauling cholesterol out of the bloodstream and, ultimately, out of the body.

The new findings contribute to a growing body of data suggesting that eggs shouldn't be construed "as a dietary evil."

Not all people respond similarly to cholesterol. Studies have shown that 30 to 40 percent of any given population is made up of "hyperresponders." In these people, blood-cholesterol concentrations spike disproportionately in response to dietary cholesterol. The study team decided to investigate whether such people put an egg's cholesterol into different-sized lipoproteins than most other people do.

So, the team recruited 29 postmenopausal women and 13 elderly men to take part in a dietary trial. None was taking cholesterol-lowering medicine at the time of the study, the author notes, which means that for a population of middle-aged-to-elderly people, the group was relatively heart healthy.

For 30 days, each volunteer received a liquid-egg product or a fat-and-cholesterol-free, protein-rich egg substitute in portions comparable to three large eggs per day. The real-egg ration delivered some 640 mg of cholesterol; the egg substitute contained no cholesterol. None of the participants knew which food he or she was getting until the end of the study.

After a month on the first diet, all volunteers took a 3-week breather and then resumed participation. For the second phase, each person received the alternative to the product he or she had initially received.

Throughout both phases of the trial, the amount of both HDL and LDL lipoproteins remained unchanged. However, the 15 hyperresponders among the volunteers had much higher amounts of cholesterol circulating with their lipoprotein particles while they were eating real eggs. "All of the increase went into large [lipoprotein] particles."

In contrast, among normal responders, only small increases in blood cholesterol occurred during the egg diet, and the size of LDL- and HDL-cholesterol particles covered the full range of lipoprotein sizes.

Not only did the two groups handle the eggs' cholesterol differently, but the hyperresponders handled the excess that showed up in their blood "in the most anti-atherogenic way"—by depositing it in the largest lipoproteins. The take-home message is that an LDL-cholesterol reading that ignores lipoprotein size may exaggerate the heart risks posed by eggs' cholesterol.

It's time to tell your healthcare provider to update his or her dietary recommendations.

Still nervous despite studies like this one? Then, try omega-3 eggs. You can now get them at most grocery chains.

Also, consider eggs to boost weight loss.

Wednesday, May 03, 2006

Insulin, NOT SODIUM, and hypertension

Insulin rather than salt is the major driver of hypertension, according to an analysis of data from a prospective study of 23 patients with confirmed atherosclerotic cardiovascular disease.

In the study, obese patients consuming a high saturated fat, low starch diet increased daily sodium intake from less than 2 grams a day to more than 20 grams a day. But they also lost an average of 5.5 kg-or about 5% of their total body weight-in six weeks.

"At the same time there were dramatic and significant reductions in fasting insulin and in mean arterial pressure, researchers said. The finding strongly suggests that "we need to stop paying so much attention to sodium and pay much more attention to fasting insulin." Insulin rises in response to a high carbohydrate, high calorie diet.

"It all comes back to obesity." Asked whether a similar weight loss achieved with a restricted calorie diet or a low fat diet could produce the same results, they agreed that it could.

"We are testing that hypothesis with a new study that will begin enrollment this summer," authors said. "We will be comparing the high fat, no-calorie-restriction diet, to a low fat diet plus Xenical (orlistat)."

And, insulin resistance has now been linked to Alzheimer's.

More on insulin resistance.

Monday, May 01, 2006

Treating periodontal disease cuts heart risk

Researchers aimed to estimate the effect of periodontal therapy on traditional and novel cardiovascular risk factors in systemically healthy individuals who have periodontitis.

A standard course of periodontal therapy (subgingival scaling and root planing) including the adjunctive use of a locally delivered antimicrobial, IPT, resulted in significant reductions in a cluster of inflammatory markers at 1 and 2 months together with an improvement in lipid markers at 2 and 6 months after therapy compared to subgingival scaling and root planing alone.

Intensive periodontal therapy produced greater reductions in IL-6 at 1 and 2 months, together with decreases in C-reactive protein and total cholesterol. Moreover, a 7 +/- 3-mm Hg decrease in systolic BP was observed at 2 months in the IPT group. Intensive periodontal therapy subjects exhibited a 1.53% +/- 1.20% and 2.00% +/- 1.42% decreases in cardiovascular risk scores (Framingham) at 2 and 6 months, respectively, when compared to those in the standard group.

The findings suggest that intensive periodontal treatment reduces systemic inflammatory markers and systolic BP, and improves lipid profiles with subsequent changes in cardiovascular risk when compared to standard therapy.

Twice a year dental visits.....a must.