26 June 2010

Nutrition and Breast Cancer

Thanks to recent research in nutrition, dietary strategies are helping many more women survive breast cancer and go on to live long, healthy lives. 

Often enough, evidence reveals these strategies may work by influencing inflammation, the immune system, and insulin responsiveness. However, there is no nutritional therapy that is yet "proven" to treat cancer directly or increase survival.

According to large trials of diet and breast cancer such as the Women's Healthy Eating and Living (WHEL) randomized trial and the Women's Intervention Nutrition Study (WINS) trial, as well as small intervention studies, a lower calorie diet leading to controlled weight reduced mortality. 

The reason - being overweight or obese appears to increase mortality because of higher risk of metastasis. Crash dieting is not the key, only healthy weight loss and patients should consult a nutritionist for planning meals. 

Patients should note that diets too low in calories can lead to loss of muscle mass, which is already a side effect of chemotherapy, and that generally leads to an increase in fat mass. 

As far as types of foods, red meat should be avoided because it's associated with increased risk of breast cancer. Saturated fat should be avoided as much as possible since it increases estrogenic stimulation of breast cancer growth. 

A low-fat, high-fiber diet is associated with suppressed estradiol levels. The diet should be based on plenty of plant-based proteins (soy, wheat), eggs, fish and low-fat dairy (whey). 

High-carb diets are also associated with increased mortality, but so are very low-cab diets. The diet should focus on obtaining a moderate amount of complex carbs (mainly from whole grains, fruits, and vegetables) rich in fiber. Blood sugar control is encouraged through eating complex carbs and obtaining regular exercise. 

Patients should seek to obtain higher levels of long-chain omega-3 fatty acids (DHA and EPA) such as from fish oil because low levels are associated with more proinflammatory markers. 

Because high dietary intake of fruits and vegetables are associated with greater breast cancer survival, it's easy to suggest that taking supplements of phytochemicals may increase survival. However, meta-analyses suggest no single vitamin/phytochemical solely improves outcomes. Instead it's best to focus on consuming more of whole fruits and vegetables.

Phytoestrogens such as from soy (isoflavones) and flax may, in fact, lower risk of breast cancer and improve survival of breast cancer. Because they mimic estrogen and bind to estrogen receptors, they may inhibit cancer cell growth. However, more research is needed before suggesting as a treatment especially in high-risk women and postmenopausal estrogen-receptive positive breast cancer patients.  Note that it could be that simply replacing meats with soy foods leads to weight management that increases breast cancer survival.

Eating foods rich in iodine such as sea vegetables or using iodized salt may anticarcinogenic effect possibly by optimizing thyroid function. Additionally, maintaining a high vitamin D status may help reduce risk cancer and improve prognosis although more research is needed to understand the relationship.  

Reference 

Kohlstadt I. Food and Nutrients in Disease Management. Boca Raton, FL: CRC Press, 2009.

11 June 2010

10 Steps for Patients with Cholesterol-Induced Cardiomyopathy

Cardiomyopathy is characterized by a weakened, enlarged or inflamed cardiac muscle. The disease may be in primary stages (asymptomatic) or secondary stages (symptoms such as shortness of breath, fatigue, cough, orthopnea, nocturnal dyspnea or edema) with main types being dilates, hypertrophic, restrictive, or arrhythmogenic (1). Treatment may include drugs such as ACE inhibitors and beta blockers, implantable cardioverter-defibrillators, cardiac resynchronization therapy, or heart transplant (1). Factors leading to cardiomyopathy may include alcohol consumption, smoking, obesity, sedentary lifestyle, smoking and high-sodium diet (1).

Hypercholesterolemia can lead to fatty streaks in blood vessels that result in decreased flow of blood through arteries. The advent of hypercholesterolemia may be directly related to cardiomyopathy as it’s well established as a risk factor in inducing systolic and diastolic dysfunction (2). Statins such as Lovastatin are commonly prescribed because of efficacy for lowering cholesterol levels and they act by inhibiting HMG-CoA reductase to deplete mevalonate (3). Mevalonate, a precursor to cholesterol is also a precursor to coQ10 and squalene (4). Mevalonite, however, is also the precursor to coQ10 and squalene. Both of these are vital nutrients with profound effects on the body.

Patient Recommendations

I would advise a patient with cholesterol-induced cardiomyopathy to adhere to the following protocol:

1. Quit smoking – If the patient smokes, he is doing himself a grave disservice as smoking can increase oxidation of cholesterol leading to atherosclerosis. It may be an underlying factor in his cardiomyopathy.

2. Regular exercise – If the patient doesn’t exercise already, then he should begin an exercise program to strengthen his heart. I would advise only short periods of exercise combined with adequate rest as opposed to aerobic training because it would prevent exhaustion or excessive stress on the heart (9).

3. Get blood pressure checked regularly – Hypertension can be present without any symptoms and can be an etiological factor in cardiomyopathy. At ages past 60 there begins to be a higher risk of developing hypertension as well as declining muscle mass replaced by fat mass. A DASH eating plan (low-fat dairy products, lean meats, rich in fruits and vegetables) can assist in lowering or maintaining healthy blood pressure levels.

4. Lose weight if necessary – Overweight and obesity is an additional risk factor for hypertension (and hypercholesterolemia) because it increases volume of blood flowing through blood vessels. Along with exercise and a DASH eating plan, a weight-management program to lower calories steadily for 1-2 pounds per week can help a person lose weight effectively and safely.

5. Eat a diet high in soluble fiber – Diets high in soluble fiber are associated with lower levels of cholesterol. Soluble fiber such as from oats and psyllium hulls are shown to reduce blood cholesterol by inhibiting absorption of cholesterol from food as well as reabsorption of cholesterol through enterohepatic circulation.

6. Supplement with coQ10 (100 mg) – CoQ10 production peaks in the mid-20s and begins to decline with only around 50 percent production in patients past age 60. Additionally, statin therapy creates further decline in coQ10 synthesis for reasons discussed above. This patient could benefit from regular daily coQ10 supplementation in 100 mg doses. The CoQ10 will serve to support creation of energy and mitochondrial biogenesis in cardiac tissue to help maintain strong heart function.

7. Enjoy enough sunshine and take a vitamin D supplement – As people become older they are more susceptible to vitamin D insufficiency or deficiency, which as discussed earlier may lead to a weakened heart as suggested by emerging studies. Support for heart health can be achieved by keeping 25(OH)D to levels in the plasma to “sufficient” amounts (32 ng/mL) through sensible sun exposure (maybe along with exercise) and/or supplementation with vitamin D.

8. Supplement with D-ribose and l-carnitine – Both supplements can support elevated energy levels in cardiac tissue leading to improved heart function. In a randomized, double-blind crossover trial, D-ribose has been shown to improve diastolic function parameters and improve quality of life in patients with cardiomyopathy (10). L-carnitine combined with coQ10 and omega-3 fatty acids has been shown to improve cardiac function in dilated cardiomyopathy (11).

9. Eat leafy greens – Apart from the extra dietary fiber, the magnesium in leafy greens can be an additional support for heart health. Magnesium has a role in supporting healthy blood pressure levels and regulating heart function (12).

10. Eat fish regularly or take a quality fish oil supplement (4g daily) – Greater levels of EPA and DHA omega-3 fatty acids in the diet combined with coQ10 and l-carnitine has been shown in research to improve cardiac function in dilated cardiomyopathy (11).

Reference List

1. Wexler RK, Elton T, Pleister A, Feldman D. Cardiomyopathy: an overview. Am Fam Physician 2009;79:778-84.

2. Huang Y, Walker KE, Hanley F, Narula J, Houser SR, Tulenko TN. Cardiac systolic and diastolic dysfunction after a cholesterol-rich diet. Circulation 2004;109:97-102.

3. Littarru GP, Langsjoen P. Coenzyme Q10 and statins: biochemical and clinical implications. Mitochondrion 2007;7 Suppl:S168-S174.

4. Scharnagl H, Marz W. New lipid-lowering agents acting on LDL receptors. Curr Top Med Chem 2005;5:233-42.

5. Jeya M, Moon HJ, Lee JL, Kim IW, Lee JK. Current state of coenzyme Q(10) production and its applications. Appl Microbiol Biotechnol 2010;85:1653-63.

6. Caso G, Kelly P, McNurlan MA, Lawson WE. Effect of coenzyme q10 on myopathic symptoms in patients treated with statins. Am J Cardiol 2007;99:1409-12.

7. Visvanathan R, Chapman I. Preventing sarcopaenia in older people. Maturitas 2010.

8. Ahmed W, Khan N, Glueck CJ et al. Low serum 25 (OH) vitamin D levels (<32 ng/mL) are associated with reversible myositis-myalgia in statin-treated patients. Transl Res 2009;153:11-6.

9. Kohlstadt I. Food and Nutrients in Disease Management. Boca Raton, FL: CRC Press, 2009.

10. Omran H, Illien S, MacCarter D, St Cyr J, Luderitz B. D-Ribose improves diastolic function and quality of life in congestive heart failure patients: a prospective feasibility study. Eur J Heart Fail 2003;5:615-9.

11. Vargiu R, Littarru GP, Faa G, Mancinelli R. Positive inotropic effect of coenzyme Q10, omega-3 fatty acids and propionyl-L-carnitine on papillary muscle force-frequency responses of BIO TO-2 cardiomyopathic Syrian hamsters. Biofactors 2008;32:135-44.

12. Gropper SS, Smith JL, Groff JL. Advanced Nutrition and Human Metabolism. Belmont, CA: Thomson Wadsworth, 2009.

05 June 2010

Low muscle mass linked to diabetes


Being overweight is a risk factor for type 2 diabetes; however, a new study shows losing weight alone may not be enough to reduce risk of type 2 diabetes in people with low muscle mass and strength, particularly if they are over the age of 60.

These are the findings of new research from Dr. Preethi Srikanthan of University of California, Los Angeles, and colleagues who performed a cross-sectional analysis of 14,528 people from National Health and Nutrition Examination Survey III.

Dr. Srikanthan and colleagues concluded that age-related muscle loss, or sarcopenia, was associated with greater insulin resistance; and, sarcopenia, independent of obesity, may be an early predictor of diabetes. This association of sarcopenia and insulin resistance was strongest in those who were 60 years and older, the researchers warn.

Apart from these poor health outcomes, sarcopenia in older adults is also clearly associated with other health outcomes such as increased risk of falls, hip fractures, bone loss (osteopenia) and physical disability.
Several earlier studies suggest similarly that a direct correlation exists between sarcopenia in people ages 60 and older and greater risk of insulin resistance, metabolic syndrome, type 2 diabetes and cardiovascular disease, regardless of body weight.

Study Reference: Srikanthan P, Hevener AL, Karlamangla AS, 2010 Sarcopenia Exacerbates Obesity-Associated Insulin Resistance and Dysglycemia: Findings from the National Health and Nutrition Examination Survey III. PLoS ONE 5(5): e10805. doi:10.1371/journal.pone.0010805

04 June 2010

Briefly on Detoxification Systems

Every day we are exposed to toxins, or xenobiotics, that are found in our food, water and environment. The body also makes toxins within itself. These all must be either stored such as in muscle or fat or they are  detoxified and eliminated via the feces or urine.

The body's main detoxification organ is the liver, but can also happen in the intestine and other organs. The detoxification systems handle a wide range of compounds mainly by two steps: phase I and phase II detoxification. 

Phase I detoxification is a reaction that entails functionalization of the compound, breaking it down. The major P450 enzymes are generally involved in phase I detoxification. Most major drugs and exogenous toxins are metabolized this way. At times the product of phase I detoxification can be more harmful than the original product.  

Phase II detoxification is a second reaction that generally follows phase I detoxification. It entails transforming a phase I reactant through conjugation (typically to an amino acid, such as in glucuronidation or sulfation) to become water soluble. When it's water-soluble, the toxin can be excreted in the urine. 

Although the phases of detoxification are not yet well understood, it is clear through observational studies that there are a variety of factors that can inhibit or induce detoxification. An inducer of detoxification can be a a toxin itself or a compound in the diet. 

In a typical detoxification support plan, a nutritionist may suggest various nutrients to support or upregulate phase I cytochrome P450 enzymes and phase II conjugation pathways. 

The plan would generally seek to increase glutathione levels in the body such as with n-acetyl cysteine or cysteine or spare glutathione such as with silymarin. 

The plan may also support detoxification in other ways by increasing antioxidant status with coenzyme Q10, vitamin A, vitamin C, or selenium. Or, it may provide B vitamins to act as co-factors for enzymes.  

Reference

http://www.thorne.com/altmedrev/.fulltext/3/3/187.pdf