Saturday, August 22, 2009

Nutrition Hodgepodge

It's been a busy week. I attended a Conversation MAPS training by Merck for diabetes education on Tuesday night. I got my own set of 5 maps and I'm going to start facilitating sessions next month with my patients. These maps are AWESOME! Check out HealthyI for training sessions near you. If you work with a diabetic population, or just want an awesome set of educational tools free of cost, attend one of these sessions -- it was so rewarding!

Because there's so much I want to blog about today, consider this a hodgepodge of nutrition-related news. Here we go!

First up: cholesterol-lowering supplements [1]
Of course there's a TON of supplements on the market touting to be the ultimate cholesterol-lowering aid. Please note, supplements are meant to be used
in addition to healthy diet and regular exercise regimens! Additionally, what works for one individual may not work for the next. Please consider the role an unconscious change in diet and/or a placebo affect can alter results of supplement-taking persons [1].

1. Artichoke leaf extract (also known as Cynara scolymus).

  • The good: In 2000, a randomized, double-blind, placebo-controlled trial including 150 "high risk" adults (cholesterol > 280) was performed. The trial lasted 6 weeks and LDL-cholesterol (the bad) dropped 23% compared to the placebo group.
  • The bad: The results are yet to be replicated. Similar studies show a decrease in cholesterol (-4%), but no major impacts on LDL or HDL have been found.
  • The bottom line: Few studies conducted, mixed results, don't expect miracles.
2. Fenugreek.

  • The good: Studies from the 1990's show a drop in total cholesterol and LDL, and in some cases, significant drops (as much as -38% in LDL). Fenugreek contains20-50% fiber and thus cholesterol-lowering effects may be attributable to this fact, if nothing else.
  • The bad: The studies were small and poor quality questioning the validity of results noted above.
  • The bottom line: Not enough evidence to support the cholesterol-lowering effects of this supplement.
3. Fiber (soluble - found in oats, barley, bran, peas, citrus fruits, and dietary supplements).

  • The good: A 1999 meta-analysis performed by Harvard Medical School researchers contained nearly 70 clinical trials assessing the effectiveness of soluble fiber in cholesterol reduction. High soluble fiber intake was associated with reducing in both total and LDL cholesterol in 60-70% of the studies examined. For each gram of soluble fiber added to participant diets, and overall reduction in LDL was estimated at 2 points (in an average of 7 weeks).
  • The bad: That's a lot of fiber. The current recommended guidelines state 25 grams of dietary fiber and the typical intake is comprised of a mere 20% soluble fiber. For example, 3 bowls of oatmeal will provide a measly 3 grams of soluble fiber. Supplements? Fine, but many experience GI upset and some prescription interferences.
  • The bottom line: A diet high in soluble fiber can lower LDL-cholesterol, however, the drop in LDL will be relatively modest.
4. Fish oil (this is the one I was most interested in reading about!) - also known as omega-3's or EPA and DHA.

  • The good: In clinical trials assessing dosing of 3 or more grams, fish oils have been shown to lower triglyceride levels by 10-30%.
  • The bad: While fish oils do not lower LDL, they have been shown to sometimes cause the opposite: a small rise in LDL-cholesterol.
  • The bottom line: Fish oils do lower triglycerides, especially in individuals with high triglycerides. The American Heart Association recommends those with high triglycerides consume 2-4 grams of fish oil a day. Those with heart disease should consume approximately 1 grams a day of EPA and DHA (combined), preferably through the diet and the consumption of fatty fish, such as salmon.
5. Garlic (oil, extract, pill, or natural state).

  • The good: A 2000 report on garlic's impact on cardiovascular risk factors showed a small (but measurable) drop in LDL and total cholesterol.
  • The bad: Studies to follow showed less encouraging results. A well-executed study performed in 2007 compared raw garlic and commercial garlic supplements over a 6 month period and found no measurable effects in total cholesterol, LDL, HDL, or triglycerides versus the placebo.
  • The bottom line: Garlic may lower LDL temporarily but its meaningful effect on cholesterol long-term is questionable.
6. Red yeast rice - a fungus that grows on rice and contains a small amount of lovastatin (a type of statin found in prescription meds).

  • The good: Compared to most supplements, evidence in support of red yeast rice is strong. Several high-quality trials have shown red yeast rice to lower LDL-cholesterol by 20-30%, comparable to a statin drug. A 2009 trial performed on patients discontinuing the use of statin drugs, red yeast rice showed a 15% and 21% decrease in total cholesterol and LDL, respectively. Cool.
  • The bad: The amount of lovastatin in the supplements vary widely across brands.
  • The bottom line: Red yeast rice is a potentially effective way to lower cholesterol, but its potency varies dramatically. Due to safety concerns with statin use, experts discourage the use of off-the-shelf red yeast rice.
The cliff notes version of the rest...

7. Ginseng

  • The bottom line: There is not enough evidence to support the use of ginseng for lowering cholesterol.
8. Guggul

  • The bottom line: More research is needed; there is not enough evidence to justify the cholesterol-lowering effects of guggul.
9. Niacin
  • The bottom line: Niacin boosts HDL (the good), but you should NOT take it without consulting a doctor. Niacin should not be used in lieu of a prescription due to potentially serious side effects.
10. Soy protein

  • The bottom line: Soy protein lowers LDL slightly.

Next up, mercury found in ALL fish caught in US streams (!)
The government tested fish caught from 300 streams in the US. All the streams contained fish contaminated with mercury and thus the U.S. Geological Survey's research launches a comprehensive examination of mercury contamination [2]. Should this worry us? Maybe so. It was shown that 27% of the fish contaminated contained levels of mercury deemed unsafe by the Environmental Protection Agency for the average fish eater, consuming fish twice weekly. Mercury is a neurotoxin which is especially dangerous to neurological development in infants and fetuses [2]. The waters in urban areas, surprisingly, were less contaminated than those in costal plain streams fed by wetlands and forests, especially in North and South Carolina, Georgia, Florida, and Louisiana. The fish most highly contaminated included bass while the lowest levels of mercury were found in brown, rainbow-cutthroat trout and channel catfish [2]. To check for fish consumption advisories in your area, go here [2].

And up last, some reading material to leave you with. Is saturated fat being falsely accused? Read more!

I had planned to talk about myths surrounding egg consumption, but I'm out of time... it's off to the dog park.
Hope Lily get some energy on the ride over! Have a wonderful weekend!

[1]. Hainer, Ryan. Cholesterol-Lowering Supplements: What Works, What Doesn't. CNN Health. August 20, 2009.
[2]. Weise, Elizabeth. Mercury Found In All Fish Caught in U.S.-Tested Streams. USA Today. August 22, 2009.

2 comments:

  1. Great post! I learned a lot about each of those in my supplement class. It's good to let the truth be known, as many people think some of those are "the end all cure all"...when in reality they aren't. I'm not sure I agree with the fact that there are only 3 grams of soluble fiber in 3 cups of oats...unless you are taking about once they are already cooked. Anyway, thanks for the info!

    ReplyDelete
  2. I just found your blog and I love it! I'm in school to be a registered dietitian so it's always so wonderful to connect to people like yourself...I love hearing all the different view points about diet, health and nutrition. I look forward to reading more!

    ReplyDelete