All posts by william-davis

If you'd like to reduce LDL cholesterol with nearly as much power as a statin drug, think thyroid.

When thyroid is corrected to ideal levels, LDL cholesterol drops 20, 30, 40 mg/dl or more, depending on how poor thyroid function and how high LDL are at the start. The poorer the thyroid function (the higher the TSH or the lower the T3 and T4) and the higher the LDL cholesterol, the more LDL drops with thyroid correction.

(For those of you minding LDL particle size, such as Track Your Plaque Members, the "dominant" LDL species will drop: If you are genetic small LDL, small LDL will drop. If you have mostly large LDL because of being wheat-free and sugar-free, then large LDL will drop.)

One of the problems is that many healthcare providers blindly follow what the laboratory says is "normal" or the "reference range," which is usually nothing more than a population average (actually the mean +/- 2 standard deviations, a common method of developing references ranges). In other words, a substantial degree of low thyroid function, or hypothyroidism, can be present when your doctor adheres to the reference range provided by the laboratory.

What does it mean to achieve ideal thyroid status? My list includes:

--Normal oral temperature of 97.3 F first upon arising. (The thyroid is the body's thermoregulatory organ.)
--TSH 1.0 mIU/L or less
--Free T3 upper half "normal" range
--Free T4 upper half "normal" range
--You feel good: mental clarity, energy, upbeat mood. You lose weight when you try.

Iodine replacement should be part of any thyroid health effort. Iodine is not an optional trace mineral, no more than vitamin C is optional (else your teeth fall out). The only dangers to iodine replacement are to those who have been starved of iodine for many years; increase iodine and the thyroid can over-respond. I've seen this happen in 2 of the last 300 people who have supplemented iodine.

In my view, neglecting T3 replacement is absurd. While it is not clear to me why many otherwise healthy people have low T3 at the low range of "normal" or even in the below-normal range, people feel better and have better health--faster weight loss, reduced LDL, reduced triglycerides, they are happier and enjoy more energy--when T3 is increased to the upper half of the reference range. (Crucial question: Why is th

You've come a long way, baby

3. jun 2011 William Davis (16)

In 1945, the room-sized ENIAC vacuum tube computer was first turned on, women began to smoke openly in public, and a US postal stamp cost three cents. And this was the US government's advice on healthy eating:

Green and yellow vegetables; oranges, tomatoes, grapefruit; potatoes and other vegetables and fruits; followed by milk and milk products; meat, poultry, fish, or eggs; bread, flour, and cereals, butter and fortified margarine.

In 2011, the computing power of the ENIAC can be performed by a microchip a few millimeters in width, smoking is now banned in public places, and a first class postage stamp has increased in price by 1466%. And this is the new USDA Food Plate for Americans:

Have we made any progress over the past 65 years? We certainly have in computing power and awareness of the adverse effects of smoking. But have US government agencies like the USDA kept up with nutritional advice? Compare the 2011 Food Plate with the dietary advice of 1945.

It looks to me like the USDA has not only failed to keep up with the evolution of nutritional thought, but has regressed to something close to advising Americans to go out and buy stocks on the eve of the 1929 depression. Most of us discuss issues like the genetic distortions introduced into wheat, corn, and soy; the dangers of fructose; exogenous glycoxhat 1 in 1000 CT studies of the chest, abdomen, or pelvis may result in cancer.”

Richard C. Semelka, MD

Professor and Vice Chairman, Department of Radiology

University of North Carolina–Chapel Hill

Is this just hype to generate headlines? Or is the truth buried in the enormous marketing clout of the medical device industry, among which the imaging device manufacturers reign supreme?

It’s been over 110 years since radiation was first used for medical imaging. Over those years, it has had its share of misadventures.

In the 1930s and 1940s, before the dangers of radiation were recognized, shoe shoppers had shoes fitted using an x-ray device of the foot to assess fit. High doses of radiation were used to shrink enlarged tonsils and extinguish overactive thyroid glands. Attitudes towards radiation were so lax that doctors commonly permitted themselves to be exposed without protection day after day, year after year, until an unexpected rise in blood cancers like leukemia was observed. As recently as the 1970s and 1980s, cancers like Hodgkins’ disease were treated with high doses of radiation, also leading to radiation-induced diseases decades later.

Not all radiation is bad. Radiation can also be used as a therapeutic tool and even today remains a useful and reasonably effective method to reduce the size, sometimes eliminate, certain types of cancer. Forty percent of people with cancer now receive some form of radiation as part of their treatment (Ron E 2003).

Just how much does medical radiation add to our exposure?

Estimates vary, but most experts estimate that medical imaging provides approximately 15% of total lifetime exposure. In other words, radiation exposure from medical imaging is simply a small portion of total exposure that develops over the years of life. Exposure can be much higher, however, in a specific individual who undergoes repeated radiation imaging or treatment of one sort or another.

For all of us, exposure to medical radiation is part of lifetime exposure from multiple sources, added to the radiation we receive from the world around us. Just by living on earth, we are exposed to radiation from space and naturally-occurring radioactive compounds, and receive somewhere around 3.0 mSv per year (U.S. Nuclear Regulatory Commission). (Doses for radiation exposure are commonly expressed in milliSieverts, mSv, a measure that reflects whole-body radiation exposure.) People living in high-altitude locales like Colorado get exposed to an additional 30–50% ambient radiation (1.0–1.5 mSv more per year).

Much of the information on radiation exposure comes from studies like the Life Span Study that, since 1961, has tracked 120,000 Japanese exposed to radiation from the atomic bombs dropped in 1945 (Preston DL et al 2003). Although regarded as a high-dose exposure study for obvious reasons, there are actually thousands of people in this study who were exposed to lesser quantities of radiation (because of distance from the bomb sites) who still display a “dose-response” increased risk for cancer many years later in life. Radiation exposures of as little as 5–20 mSv showed a slight increase in lifetime risk.

Occupational and excessive medical exposure to radiation also provides a “laboratory” to examine radiation risk. Miners exposed to radon gas; patients exposed to the imaging agent, Thorotrast, containing radioactive isotope thorium dioxide and used as an x-ray contrast agent in the 1930s and 1940s and possesses the curious property of lingering in the body for over 30 years after administration; radium injections administered between 1945 and 1955 to treat diseases like ankylosing spondylitis and tuberculosis, all provide researchers an opportunity to study the long-term effects of various types of radiation exposure over many years (Harrison JD et al 2003).

The excess exposure of workers and several hundred thousand nearby residents to the Mayak nuclear plant in Russia has also revealed a “dose-response” relationship, with increasing exposure leading to more cancers, including leukemia and solid cancers of the bone, liver, and lung (Shilnikova NS et al 2003). Nuclear waste released into the Techa river between 1948 and 1956 contaminated drinking water used by over 100,000 Russians. A plant explosion in 1957 also released an excess of radiation into the atmosphere, yielding exposure via inhalation. Some sources estimate that at least 272,000 people have been affected by radiation from the Mayak plant. This unfortunate situation has, however, yielded plenty of data on radiation exposure and its long-term effects.

It’s also been known for several decades that people who receive therapeutic radiation for treatment of cancer, even with the reduced doses now employed, are subject to increased risk of a second cancer consequent to the radiation treatment.

From experiences like this, radiation experts estimate that an exposure of 10 mSv increases a population’s risk for cancer by 1 in 1000 (Semelka RC et al 2007).

This question was recently thrust into the spotlight with publication of a study from Columbia University in New York suggesting that a 20-year old woman would be exposed to a lifetime risk of cancer as high as 1 in 143 consequent to the radiation received during a CT coronary angiogram. (Important note: This was estimated risk from a CT coronary angiogram, not a simple heart scan that we advocate for the Track Your Plaque program.) The risk at the low end of the spectrum would be in an 80-year old man (because of the shorter period of time to develop cancer), with a risk of 1 in 5017. If “gating” to the EKG is added (which many scan centers do indeed perform nowadays), risk for a 60-year old woman is estimated at 1 in 715; risk for a 60-year old male, 1 in 1911 (Einstein AJ et al 2007). This study generated some criticism, since it did not directly involve human subjects, but used “phantoms” or x-ray dummies to simulate x-ray exposure. Nonetheless, the point was made: CT coronary angiograms in current practice do indeed expose the patient to substantial quantities of radiation, sufficient to pose a lifetime risk of cancer.

The media frenzy

The NY Times ran an article called With Rise in Radiation Exposure, Experts Urge Caution on Tests in which they stated:

"According to a new study, the per-capita dose of ionizing radiation from clinical imaging exams in the United States increased almost 600 percent from 1980 to 2006. In the past, natural background radiation was the leading source of human exposure; that has been displaced by diagnostic imaging procedures, the authors said."

“This is an absolutely sentinel event, a wake-up call,” said Dr. Fred A. Mettler Jr., principal investigator for the study, by the National Council on Radiation Protection. “Medical exposure now dwarfs that of all other sources.”

Radiation is a widely used imaging tool in medicine. Although CT scans of the brain, bones, chest, abdomen, and pelvis account for only 5% of all medical radiation procedures, they are responsible for nearly 50% of medical radiation used. It’s been known for years that increasing radiation exposure increases cancer risk over many years, but the boom of newer, faster devices that provide more detailed images has opened the floodgates to expanded use of CT scanners.

But before we join in the hysteria, let's first take a look at exposure measured for different sorts of tests:

Typical effective radiation dose values for common tests

Computed Tomography

Head CT 1 – 2 mSv
Pelvis CT 3 – 4 mSv
Chest CT 5 – 7 mSv
Abdomen CT 5 – 7 mSv
Abdomen/pelvis CT 8 – 11 mSv
Coronary CT angiography 5 – 12 mSv

Non-CT

Hand radiograph Less than 0.1 mSv
Chest radiograph Less than 0.1 mSv
Mammogram 0.3 – 0.6 mSv
Barium enema exam 3 – 6 mSv
Coronary angiogram 5 – 10 mSv
Sestamibi myocardial perfusion (per injection) 6 – 9 mSv
Thallium myocardial perfusion (per injection) 26 – 35 mSv

Source: Cynthia H. McCullough, Ph.D., Mayo Clinic, Rochester, MN

A plain, everyday chest x-ray, providing less than 0.1 mSv exposure, provides about the same quantity of radiation exposure as flying in an airplane for four hours, or the same amount of radiation from exposure to our surroundings for 11–12 days. Similar exposure arises from dental x-rays.

If you have a heart scan on an EBT device, then your exposure is 0.5-0.6 mSv, roughly the same as a mammogram or several standard chest x-rays.

With a heart scan on a 16- or 64-slice multidetector device, exposure is ideally around 1.0-2.0 mSv, about the same as 2-3 mammograms, though dose can vary with this technology depending on how it is performed (gated to the EKG, device settings, etc.)

CT coronary angiography presents a different story. This is where radiation really escalates and puts the radiation exposure issue in the spotlight. As Dr. Cynthia McCullough's chart shows above, the radiation exposure with CT coronary angiograms is 5-12 mSv, the equivalent of 100 or more chest x-rays or 20 mammograms. Now, that's a problem.

The exposure is about the same for a pelvic or abdominal CT. The problem is that some centers are using CT coronary angiograms as screening procedures and even advocating their use annually. This is where the alarm needs to be sounded. These tests, as wonderful as the information and image quality can be, are not screening tests. Just like a pelvic CT, they are diagnostic tests done for legitimate medical questions. They are not screening tests to be applied broadly and used year after year.

It’s also worth giving second thought to any full body scan you might be considering. These screening studies include scans of the chest, abdomen, and pelvis. These scans, performed for screening, expose the recipient to approximately 10 mSv of radiation (Radiological Society of North American, 2007). Debate continues on whether the radiation exposure is justified, given the generally asymptomatic people who generally undergo these tests.

Always be mindful of your radiation exposure, as the NY Times article rightly advises. However, don't be so frightened that you are kept from obtaining truly useful information from, for instance, a CT heart scan (not angiography) at a modest radiation cost.

Heart scans, CT coronary angiograms and the future

Unfortunately, practicing physicians and those involved in providing CT scans are generally unconcerned with radiation exposure. The majority, in fact, are entirely unaware of the dose of radiation required for most CT scan studies and unaware of the cancer risk involved. It is therefore up to the individual to insist on a discussion of the type of scanner being used, the radiation dose delivered (at least in general terms), the necessity of the test, alternative methods to obtain the same diagnostic information, all in the context of lifetime radiation exposure.

Our concerns about radiation exposure all boil down to concern over lifetime risk for cancer, a disease that strikes approximately 20% of all Americans. Many factors contribute to cancer risk, including obesity, excessive saturated fat intake, low fiber intake, lack of vitamin D, repeated sunburns, excessive alcohol use, smoking, exposure to pesticides and other organochemicals, asbestos and other industrial exposures, electromagnetic wave exposure, and genetics. Radiation is just one source of risk, though to some degree a controllable one.

Some people, on hearing this somewhat disturbing discussion, refuse to ever have another medical test requiring radiation. That’s the wrong attitude. It makes no more sense than wearing lead shielding on your body 24 hours a day to reduce exposure from the atmosphere. Taken in the larger context of life, radiation exposure is just one item on a list of potentially harmful factors.

It is, however, worth some effort to minimize radiation exposure over your lifetime, particularly before age 60, and by submitting to high-dose testing only when truly necessary, or when the potential benefits outweigh the risks. Thus, with heart scans and CT coronary angiography, some thought to the potential benefits of knowing your score or the information gained from the CT angiogram need to be considered before undergoing the test. Often the practical difficulty, of course, is that your risk for heart disease simply cannot be known until after the test.

In our view, in the vast majority of instances a simple CT heart scan can serve the simple but crucial role of quantifying risk for heart attack and atherosclerotic plaque. CT heart scans yield this information with less than a tenth of the radiation exposure of a CT coronary angiogram. In people without symptoms and a normal stress test, there is rarely a need for CT coronary angiography with present day levels of radiation exposure. Perhaps as technology advances and the radiation required to generate images is reduced, then we should reconsider.

Early experiences are suggesting that the newest 256-slice scanners, now being developed but not yet available, will cut the dose exposure of 64-slice CT angiograms in half (from 27.8 mSv to 14.1 mSv in a recent Japanese study). The 256-slice scanners will allow scanning that is faster over a larger area in a given period of time.

Thankfully, the scanner manufacturers are increasingly sensitive to the radiation issue and have been working on methods to reduce radiation exposure. However, it still remains substantial.

References:
Einstein AJ, Henzlova MJ, Rajagopalan S. Estimating risk of cancer associated with radiation exposure from 64-slice computed tomography coronary angiography. JAMA 2007 Jul 18;298(3):317–323.

Harrison JD, Muirhead CR. Quantitative comparisons of cancer induction in humans by internally deposited radionuclides and external radiation. Int J Radiat Biol 2003 Jan;79(1):1–13.

Hausleiter J, Meyer T, Hadamitzyky M et al. Radiation Dose Estimates From Cardiac Multislice Computed Tomography in Daily Practice: Impact of Different Scanning Protocols on Effective Dose Estimates. Circulation 2006;113:1305–1310.

Kalra MK, Maher MM, Toth TL, Hamberg LM, Blake MA, Shepard J, Saini S. Strategies for CT radiation dose optimization. Radiology 2004;230:619–628.

Mayo JR, Aldrich J, Müller NL. Radiation exposure at chest CT: A statement of the Fleischner Society. Radiology 2003; 228:15–21.

Mori S, Nishizawa K, Kondo C, Ohno M, Akahane K, Endo M. Effective doses in subjects undergoing computed tomography cardiac imaging with the 256-multislice CT scanner. Eur J Radiol 2007 Jul 10; [Epub ahead of print].

Preston DL, Pierce DA, Shimizu Y, Ron E, Mabuchi K. Dose response and temporal patterns of radiation-associated solid cancer risks. Health Phys 2003 Jul;85(1):43–46.

Ron E. Cancer risks from medical radiation. Health Phys 2003 Jul;85(1):47–59.

Shilnikova NS, Preston DL, Ron E et al. Cancer mortality risk among workers at the Mayak nuclear complex. Radiation Res 2003 Jun;159(6):787–798.

Semelka RC, Armao DM, Elias J Jr, Huda W. Imaging strategies to reduce the risk of radiation in CT studies, including selective substitution with MRI. J Magn Reson Imaging 2007 May;25(5):900–9090.

Copyright 2007, Track Your Plaque.

Goodbye, fructose

12. July 2009 William Davis (35)

A carefully-conducted study by a collaborative research group at University of California-Berkeley has finally closed the lid on the fuss over fructose vs. glucose and its purported adverse effects.

The study is published in its entirety here.

Compared to glucose, fructose induced:

1) Four-fold greater intra-abdominal fat accumulation--3% increased intra-abdominal fat with glucose; 14.4% with fructose. (Intraabdominal fat is the variety that blocks insulin responses and causes diabetes and inflammation.)

2) 13.9% increase in LDL cholesterol but double the increase for Apoprotein B (an index of the number of LDL particles, similar to NMR LDL particle number).

3) 44.9% increase in small LDL, compared to 13.3% with glucose.

4) While glucose (curiously) reduced the net postprandial (after-eating) triglyceride response (area under the curve, AUC), fructose increased postprandial triglycerides 99.2%.

The authors propose that fructose specifically increases liver VLDL production, the lipoprotein particle that yields abnormal after-eating particles, increased LDL, and provides building blocks to manufacture small LDL particles. The authors also persuasively propose that fructose metabolism, unlike glucose, is not inhibited (via feedback loop) by energy intake, i.e., it's as if you are always starving.

Add to this the data that show that fructose increases uric acid (that causes gout and may act as a coronary risk factor), induces leptin resistance, causes metabolic syndrome (pre-diabetes), and increases appetite, and it is clear that fructose is yet another common food additive that, along with wheat, is likely a big part of the reason Americans are fat and diabetic.

Fructose is concentrated, of course, in high-fructose corn syrup, comprising anywhere from 42-90% of total weight. Fructose also composes 50% of sucrose (table sugar). Fructose also figures prominently in many fruits; among the worst culprits are raisins (30% fructose) and honey (41% fructose).

Also, beware of low-fat or non-fat salad dressings (rich with high-fructose corn syrup), ketchup, beer, fruit drinks, fruit juices, all of which are rich sources of this exceptionally fattening, metabolism-bypassing, LDL cholesterol/small LDL/ApoB increasing compound. Ironically, this means that many low-fat foods meant to reduce cholesterol actually increase it when they contain fructose in any form.

When you hear or say "fructose," run the other way, regardless of what the Corn Refiners Association says.

The statin-free life

8. July 2009 William Davis (20)

Matt came to me because his doctor couldn't reduce his LDL cholesterol.

His doctor had prescribed Zocor (simvastatin), Lipitor, Crestor, even pravastatin, all of which resulted in incapacitating muscle aches and weakness within a week of starting. No surprise, Matt had a jaundiced view of statin drugs.

We started out by characterizing his lipoprotein patterns:

--LDL 155 mg/dl

--72% of LDL was small LDL, a moderately severe pattern. (This means that small LDL comprised 112 mg/dl of the total 155 mg/dl LDL; large LDL comprised 43 mg/dl--small LDL was the problem.)

--HDL 42 mg/dl --Triglycerides 133 mg/dl

--No lipoprotein(a)

Beyond lipoproteins, Matt proved severely deficient in vitamin D with a starting level of 18 ng/ml.

Matt's doctor had advised that he avoid salt, as his blood pressure had been borderline high. His thyroid assessment disclosed a TSH of 3.89 mIU/ml with thyroid hormones free T3 and free T4 in the lower half of the normal range.

I therefore asked Matt to:

--Eliminate wheat, cornstarch, and sugars to reduce small LDL
--Add iodine
--Supplement 6000 units of an oil-based vitamin D preparation
--Take fish oil to provide at least 1800 mg EPA + DHA per day
--Take Armour Thyroid 1 grain per day

Several months later on this program, Matt had a repeat basic lipid panel:

--LDL 82 mg/dl--a 47% reduction

--HDL 52 mg/dl a 24% increase

--Triglycerides 60 mg/dl--a 55% decrease

In addition, vitamin D was 66 ng/ml, TSH was <1.0 mIU/ml with free T3 and free T4 in the upper half of the "reference range." Matt also felt great.

While the numbers could be slightly better, Matt had made tremendous progress towards achieving perfect values.

There you have it: Marked correction of cholesterol values, no statin drugs involved.

Creatine: Not just for muscle heads

5. July 2009 William Davis (29)

Even if you’re not interested in building big muscles like a bodybuilder, there are health benefits to increasing muscle mass: increased bone density, better balance, and fewer injuries. Greater muscle mass means higher metabolic rate, improved insulin responsiveness, lower blood sugar. The inevitable loss of muscle mass of aging can lead to frailty, an increasingly common situation for the elderly. Muscle loss be reversed, health improved as a result.

Since its introduction in 1994, creatine has exploded in popularity, particularly among bodybuilders and athletes interested in gaining muscle mass and strength. But creatine is not just for young weight lifters. If you are just interested in increasing muscle mass for its health benefits, then creatine is something to consider.

A study of creatine supplementation in men, average age 70 years, demonstrated that, when creatine was combined with strength training, it increased muscle mass 250% better than placebo (7.26 lb muscle vs 2.86 lb muscle), along with improved leg strength and endurance. The same group also demonstrated 3.2% increased bone density (measured using dual energy X-ray absorptiometry) after 12 weeks in participants taking creatine with strength training, while the control (no strength training, no creatine) group decreased by 1.0%.

Benefits are not confined to men. Similar results were observed in another study that included women (age 65 and older), with outcomes in females comparable to males. This is especially important for females, given the common development of osteopenia and osteoporosis in postmenopausal females.

Other studies have shown that benefits are maintained after stopping creatine supplementation.

The most popular form of creatine is the monohydrate, generally taken as a “loading” phase of 15-20 grams per day (generally split into 3-4 doses of 5 grams) for 5-7 days, followed by weeks to months of 2-5 grams per day.

An alternative form, polyethylene glycosylated creatine (PEG-creatine) provides similar effects at one-fourth to one-half the dose of creatine, i.e., 1.25-2.5 grams per day.

Despite previous concerns about kidney toxicity with prolonged use, another study showed that athletes taking creatine for up to 21 months have shown no adverse effects on kidney function, lipid (cholesterol) values, or other basic health measures.

Having healthy muscle mass doesn't make you bulge like a bodybuilder. With modest efforts at strength training, augmented with creatine supplementation, you have a wonderful tool to feel better, reduce injury, increase bone density, and combat abnormal insulin resistance, not to mention accelerate weight loss, since lean muscle mass consumes energy.

The ultimate “bioidentical” hormone

2. July 2009 William Davis (19)

There has been a lot of debate over whether or not “bio-identical” hormones, i.e., hormones identical to the human form, are superior to non-human forms dispensed by the drug industry.

The FDA is currently taking steps to clamp down on availability of bioidentical hormones and their claims of superiority, despite a groundswell of grassroot support for them. The argument has pitted anti-aging practitioners and the public, as well as the likes of Oprah and Suzanne Somers, against Big Pharma and the FDA, the two forces trying to squash the bioidentical hormone movement.

Regardless of what heavy-handed approach the FDA takes, we already have access to hormones identical to the original human form. It requires no prescription and yields downstream hormones that the human body recognizes as human.

That "bioidentical" hormone is pregnenolone.

Pregnenolone is the first biochemical step in the conversion of dietary cholesterol (yes-cholesterol!) to numerous other hormones. Pregnenolone is the source of the hormones that lie at the center of the bioidentical hormone controversy: estrogens, progesterone, and testosterone. We therefore already have our own over-the-counter, non-prescription form of bioidentical hormones.

Supplemental pregnenolone increases estrogens (mildly), progesterone, and testosterone. Prenenonlone supplementation simply provide more of the basic substrate for hormone production. The increase in hormones is usually modest, not as vigorous as direct hormone replacement like, say, testosterone or progesterone topical creams. But pregnenolone can be useful when small to moderate increases are desired, such as for reduction of Lp(a). A theoretical downside is that pregnenonlone can also convert to cortisol, the adrenal gland hormone that regulates fluid and blood pressure. However, I've not seen any measurable increase in cortisol with low doses of pregnenonlone and limited data suggest that it does not. Pregnenolone also converts to the other adrenal gland hormone, DHEA; I call DHEA "the hormone of assertiveness," since some people who take too much pregnenolone (or direct DHEA) acquire excessive assertiveness.

The key to pregnenolone supplementation is to proceed gradually and begin with a small dose, e.g., 5 mg every morning. Hormonal assessment is best conducted periodically to assess the effects and to determine whether a dose adjustment is in order.