From Ronald Hoffman, MD
Choline: Little-known nutritional fact—according to a recent article in Science Daily, it’s estimated that more than 90% of Americans are not meeting the recommended daily intake of choline. We know that choline is a dietary precursor to acetylcholine, an essential neurotransmitter. In fact, certain dementia drugs are designed to amp up brain levels of acetylcholine. Adequate choline has now been recognized as essential for expectant moms; I routinely prescribe phosphatidylcholine supplements during pregnancy to assure adequate fetal brain development.
Now researchers have confirmed a link between inadequate choline intake and “a constellation of problems”—brain abnormalities, as well as enlarged livers and hearts. Moreover, there was a propensity to weight gain and blood sugar abnormalities in mice fed a choline-deficient diet.
Part of the answer may be that choline helps keep homocysteine levels low enough to minimize its toxic effects.
The study authors take issue with current dietary guidelines for choline intake which, they claim, even though most Americans don’t attain them, are insufficient for optimal metabolism.
Vegetarians may be especially prone to inadequate choline intake since they eschew rich sources like meat (especially organ meats), eggs, and poultry. Soy and Brussels sprouts may deliver some choline, but most Americans would do well to supplement, especially if embracing a plant-based diet or during pregnancy.
Live fast, die young? We’ve all heard the aphorism. But new research suggests that, when it comes to thyroid function, the old saw may be true. Scientists have recently discovered a paradox: While hypothyroidism is associated with a host of health problems, including weight gain and high cholesterol, people with exceptionally long life spans often possess one of the hallmarks of low thyroid—an elevated thyroid stimulating hormone (TSH).
When TSH is high, it’s often a tip-off that thyroid function is suboptimal. Endocrinologists have progressively lowered the TSH threshold for subclinical hypothyroidism from 10, to 5, and recently, as low as 4. Some zealous integrative doctors rush to treat anyone with a TSH less than 3 or even lower. It’s often life-changing, restoring energy and vitality, frequently facilitating weight loss and alleviating depression. For some, it’s like natural Ritalin.
On the other hand, these researchers found that a slightly high TSH in older individuals—which might tempt some doctors to prescribe thyroid hormone replacement—was a hallmark of longevity. They determined that the thyroids of these seniors was less responsive to TSH, causing it to rise accordingly while normal thyroid function was preserved.
Could it be that a slightly lower metabolic rate confers a survival benefit? “Slow and steady wins the race”, they say. Certainly seems to apply to the longest living terrestrial animals—those big lumbering tortoises that can live to 150.
The findings suggest we exercise caution in ordering thyroid for older individuals with a borderline TSH. For example, I now forego automatically reaching for the prescription pad for active 60-plus patients with a TSH of 5 or more who say they feel fine. Conservative prescribing also avoids the problem of prompting rapid heart rate—even atrial fibrillation—with excess thyroid stimulation in vulnerable seniors.
