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Integrative Medicine and Wellness

with Joe Pizzorno, Jr., ND

The Integrative Medicine and Wellness blog has now been retired. We appreciate the wisdom and support Dr. Joseph Pizzorno has brought to the WebMD community throughout the years. If you would like to talk with others about wellness, please join or start a discussion on one of our Health Exchanges.

Monday, August 20, 2007

Hydrogenated Oils and Trans Fats

How can food products containing partially hydrogenated oils be trans fat free?

For years, nutrition experts have been recommending that people avoid foods with partially hydrogenated oils on the label because they contain dangerous trans fats. Now, products are appearing that contain hydrogenated oils, but are labeled “trans fat free.” Confused?

I was at a child’s birthday party this weekend, and the conversation turned, as it often does when I’m around, to nutrition and health. An old friend of mine asked me how it was that health food store-brand margarine could both contain hydrogenated oils and also claim to be trans fat free.

There are at least two ways that I’m aware of. But to understand them, we’d better take a detour into food chemistry. Unsaturated fats usually make up the bulk of vegetable oils. These fats are unsaturated because they have less hydrogen per gram than saturated fats. Unsaturated fats are cheap, but they are also liquid and less stable (spoil more quickly) than saturated fats, making a big problem for food manufacturers.

Manufacturers have made vegetable oils more solid and more stable by adding in extra hydrogen in an industrial process called hydrogenation. They traditionally haven’t added in enough hydrogen to fully saturate the fat, leading to the description “partially” hydrogenated oils. Partially hydrogenated oils are popular in processed foods because they are cheap, stable, widely available, and add a nice mouth-feel.

In this process, a small percentage of the unsaturated fats become something called trans fats, fats that are thought to have particularly destructive effects on the human body even in small amounts. For example, trans fats are thought to increase bad LDL cholesterol, decrease good HDL cholesterol, and have been correlated with increased risk of heart attack. For these reasons, and ensuing regulatory pressure, the food industry is moving away from adding hydrogenated oils into food.

So, how does a product that contains hydrogenated fats call itself trans fat free? One way is by shrinking serving size. The FDA allows products containing up to half a gram of trans fats per serving to be labeled as trans fat free. When adverse effects of intake can be seen at levels as low as two grams per day or less, those almost half-gram servings could end up being more significant than you would guess. By defining servings on the small end, fatty foods like margarines can look low calorie and trans fat free, when they are, in fact, neither.

Alternately, companies can fully saturate the vegetable oil with hydrogen, creating an all saturated fat product. Since this product is very solid, it needs to be artificially thinned down by whipping with water before using. Although fully hydrogenated oils do not contain trans fat, they are by no means a health food. Saturated fats, whether naturally occurring or produced industrially, have the same adverse effects on cholesterol as trans fats, and are potentially worse for blood sugar control.

When possible, try to use liquid fats like organic canola, safflower, or sunflower oil in cooking instead of solids. For spreads and other mildly heated items, extra virgin olive oil is often a good choice. For those recipes that require more solid fats, use the non-hydrogenated margarines sold in health food stores, or just plain old organic butter.

Matt Brignall, ND

References:

  • de Roos NM, Bots ML, Katan MB. Replacement of dietary saturated fatty acids by trans fatty acids lowers serum HDL cholesterol and impairs endothelial function in healthy men and women. Arterioscler Thromb Vasc Biol. 2001 Jul;21(7):1233-7.
  • Lichtenstein AH, Erkkila AT, Lamarche B, et al. Influence of hydrogenated fat and butter on CVD risk factors: remnant-like particles, glucose and insulin, blood pressure and C-reactive protein. Atherosclerosis. 2003 Nov;171(1):97-107.
  • Odegaard AO, Pereira MA. Trans fatty acids, insulin resistance, and type 2 diabetes. Nutr Rev. 2006 Aug;64(8):364-72.
  • Thomsen C, Rasmussen O, Lousen T, et al. Differential effects of saturated and monounsaturated fatty acids on postprandial lipemia and incretin responses in healthy subjects. Am J Clin Nutr. 1999 Jun;69(6):1135-43
  • Zaloga GP, Harvey KA, Stillwell W, Siddiqui R. Trans fatty acids and coronary heart disease. Nutr Clin Pract. 2006 Oct;21(5):505-12.

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Technorati Tags: trans fat, partially hydrogenated oil, healthy diet, health and wellness

Posted by: Joe Pizzorno, Jr., ND at 9:41 am

Monday, August 13, 2007

When Does Organic Not Mean Organic?

Photo Credit: John/FrenchDuck
Answer: When it refers to fish.

For most foods bought in the United States, “organic” is short-hand for foods that meet the standards for USDA organic certification. For fruits, vegetables, and other plant foods, there are well-crafted standards around soil, pest management, and post-harvest handling and processing required for certification. For animal foods, requirements include the same well-crafted standards involving organically grown feeds, animal husbandry practices, and stringent production and handling specifications. Organic standards also require inspection by state or private agencies working under USDA rules and regulations.

Even though the National Organics Program – started over 15 years ago in 1990 – has done a good job laying out standards for certification, it has continually wrestled with one issue that remains both its strength and its Achilles heel. That issue is sustainability.

Sustainable Is Not the Same as Organic

The word “sustainable” is most familiar to us in the world of energy, where it means energy that can be replenished in a relatively short time and without destroying the environment. Wind-power and solar power are two examples of sustainable energy. Sustainable can also be used in the realm of agriculture, where it means farming that respects ecological cycles, natural patterns in climate and unique aspects of geography.

Even though sustainable agriculture has always lain at the heart of the National Organics Program (NOP) as the guiding spirit that gave birth to the program itself, it’s never lain at the center of evolving NOP policy. Especially in the area of animal foods, the NOP has continually wrestled with the role of sustainability. For example, there have never been comprehensive requirements for certified organic beef and dairy cattle to have ongoing access to open pasture and grazing, and the idea of requiring 30% of all food to come from the open pasture for at least 120 days is an idea that’s currently being debated within organics-related organizations across the country. The natural patterns that would normally be followed by cattle have never been comprehensively written into the NOP policy on organic beef or milk. This absence of sustainability in the production of organic animal foods does not undermine the indisputable health value of these organically-produced foods, but it does reflect an ongoing challenge in the evolution of organic regulations.

Fish Pose Unique Challenges in Terms of Sustainability

The NOP has never known exactly what to do about fish. Up until now, the NOP has allowed producers of fish to market their fish as organic as long as a third party conducts the certification. Because no one has been allowed to use the green USDA organic logo, most producers have figured organic certification wasn’t worthwhile. Still, it’s possible to buy certified organic fish right now in the U.S., and two U.S. aquaculture operations produce organic seafood for sale as organic in the marketplace.

But a current controversy is brewing over regulation of seafood as organic, and it’s a controversy that brings to light the great challenges of sustainability. First, is it really alright to raise fish inside a fish farm? Isn’t that practice tantamount to denying them “open pasture?” Can a fish farm replicate natural patterns and respect ecological cycles, without resorting to chemical treatments of the water or the fish? Won’t the isolated fish habitat – however ecological in and of itself – still end up disrupting the wider configuration of lakes and rivers and oceans that surround it?

The Current Marketplace Reality

At present, this sustainability controversy – and the lack of well-defined fish standards by the NOP – has an unpredictable array of fish products in the marketplace currently being sold as organic. There are fish farms with high standards producing high-quality organic farmed fish. There are fish farms producing extremely low-quality farmed fish and hinting at higher-quality. There are wild-caught fish being sold as high-quality but obtained from significantly polluted waters. There are also wild-caught fish from relatively clean water being properly sold as high quality. Clearly, these are murky waters – so murky, in fact, that in 2005 the state of California banned all organic claims on fish until more reliable guidelines can be established. But what about in the meantime?

Here’s a summary of our marketplace approach:

  1. In general, it’s worth paying extra for foods that display the organic logo.
  2. With fish, you’re not going to find the organic logo.
  3. Until clearer guidelines are established and the logo can be displayed, paying for foods that make organic claims may not be worth extra cost. The reliability of these claims is just too much in doubt.
  4. At present, your best bet is to find a grocery or fish seller who can document fish quality, spend time talking with that person, and ask about the issues raised in this article. If you get satisfactory answers, stick with that seller, even if you have to pay a premium price. We would not be hesitant to buy certified organic fish from certain vendors who are extremely careful and fully public about their practices and quality control. Included here would be fish from several organic fish farms, as well as certain wild-caught fish.
  5. If you can’t find a high-quality seller, move fish lower down in your meal plan, to 1-2 times a week at most, and focus on the quality of the other 95% of your meal plan.

Staying On Top of Fish Quality

Because the EPA and USDA guidelines on fish safety can be so variable and confusing, pocket fish lists have become a popular and easy way to stay on top of current recommendations. The most popular and most frequently updated fish list we’ve seen comes from the Monterey Bay Aquarium.

Buck Levin, PhD, RD and Matt Brignall, ND

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Posted by: Joe Pizzorno, Jr., ND at 3:20 pm

Thursday, August 9, 2007

Fresh, Frozen or Canned?

Photo Credit: Ali Karimian

What’s healthiest? Fresh, frozen or canned foods?

In general, organic, local, fresh is best, followed by frozen, then canned. This is not an absolute rule; frozen produce can be a better choice if it was frozen shortly after picking compared to fresh produce that traveled 3,000 miles to your grocery store – and then sat in your fridge for several days before you ate it.

Canned fruits and veggies typically have added sugar or salt, and sometimes preservatives and colors, too. Draining or rinsing off this salty water does decrease the amount of salt you consume, but you also lose the water-soluble vitamins and minerals (vitamin C, B vitamins, potassium), which have leeched into the salty water. Using this water as a soup base is one way to retain some of those nutrients in your diet.

Vitamin stability is affected by heat light, air, and pH. What happens to the food before you get it (agricultural practices, maturity, storage, handling, fermentation, drying, freezing, canning, and blanching), and after you get it (home food processing, storage, purchasing practices, cooking practices, food preparation, and reheating), all affect the amount of nutrients the food delivers to you by up to 20-fold!

In general, vitamins E, C, B1, folate, and retinol are the most delicate and likely to be lost through cooking, processing or simply the passage of time. Minerals and macronutrients (protein, carbohydrate, fats) are typically the most stable and most likely to survive.
If you are serious about retaining the most nutrients, here are the details:

The Produce Department

Fruits that stay ripe, like grapes, have pretty stable vitamin content. Fruits that spoil quickly, like raspberries, lose about half their vitamin C in a week. Many vegetables lose delicate nutrients (vitamins E, C, B1, folate, and retinol) rapidly as soon as they are picked.

The Frozen Food Aisle

Commercial food is usually blanched before it is frozen. In this process, plant foods are cooked with hot water or steam for a short period of time. This decreases the water-soluble nutrients by 10-50%. Thawing further destroys vitamin C levels, so it’s best to cook frozen vegetables while they are still frozen. Leafy green vegetables lose more nutrients than other vegetables because of their large surface area. As the months pass, the produce in your freezer will continue to lose its nutrients, so you should finish it off within 6 months. Although frozen foods have lost some of their flavor, freezing is generally a good way to preserve the nutrients and texture of many foods.

The Canned Food Aisle

Foods that are going to be canned are cooked at high temperatures and usually for a longer period of time when compared to commercial freezing. The temperature and duration of cooking are crucial factors; fewer nutrients are lost when cooking at high heat for a short period of time than at low heat for a long period of time. Vitamin B2 is more sensitive to light than to heat, but this can be tightly controlled in industrial processing. Vitamins A, E and beta-carotene are susceptible to destruction by air, but this can also be controlled during industrial processing.

During canning, green peas lose about 80% of their thiamin, 73% of their vitamin C, and 35% of their folate. The amount of time canned foods spend on the shelf also affects their nutritional value. For example, the vitamin C content can decrease another 20% over the course of a year.

Unlike vitamins, minerals are not destroyed by light, heat, pH, or oxidizing agents. Minerals are removed during physical processing or may leach into water. Cooked vegetables that have been frozen for 6 months do not have iron or zinc losses.

Salmon, which is typically cooked before being put in the can and then cooked again during canning, loses some of its carotenoids during pre-canning cooking, and another 15-35% during the actual canning. Some companies place the raw, fresh fish in the can, then seal and cook only once to minimize nutrient loss. These companies tend to offer wild-caught, environmentally friendly fish but may not be stocked in your grocery store. Fortunately, you can find them on the internet.

Interestingly, the calcium content of some fish increases as a result of the canning process. Fish that are canned with their bones, like sardines, have about 10-20 times more calcium than their fresh form. During canning, the calcium-rich bones soften, so they can be easily eaten. Fish that are not canned with their bones, like tuna, lose about half their calcium due to canning. However, these fish, whose bones are not normally eaten, are not a good source of calcium anyway.

Check Out

Although there are large variations among foods and among individual nutrients within foods, it is safe to say that the more a food is processed, the more nutrients are destroyed. Your best nutritional bet is organic, local, fresh produce, followed by frozen, then canned.

Raven Bonnar-Pizzorno, MS (Nutrition)

References:

  • Bender. Changes in micronutrients due to industrial processing. Bibl Nutr. Dieta. 1985(34) 44-55.
  • Mueller HR. The effect of industrial handling on micronutrients. J. Nutr. Sci. Vitaminol. 1990;36 Suppl 1:S47-55.
  • Nursal B, Yucecan S. Vitamin C losses in some frozen vegetables due to various cooking methods. Nahrung. 2000;44(6):451-3.
  • Prochaska LJ, Nguyen XT, Donat N, Piekutowski WV. Effects of food processing on the thermodynamic and nutritive value of foods: literature and database survey. Med. Hypotheses. 2000 Feb;54(2):254-62.
  • Reddy, MB. The impact of food processing on the nutritional quality of vitamins and minerals. Adv. Exp Med Biol. 1999. 459 99-106.
  • USDA National Nutrient Database for Standard Reference, Release 19 (2006)

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Technorati Tags: fruit, vegetables, fresh frozen canned, health and wellness

Posted by: Joe Pizzorno, Jr., ND at 10:30 pm

Thursday, August 2, 2007

Cow’s Milk Counteracts Tea’s Cardioprotective Effects

Photo Credit: Naama

Adding cow’s milk to tea counteracts tea’s beneficial blood-vessel relaxing effects, shows a study published in the European Heart Journal (Lorenz M, Jochmann N, et al., January 2007).

FULL STORY:

Sixteen healthy women volunteers drank 16 ounces of either freshly brewed black tea, black tea with 10% skimmed cow’s milk, or boiled water as a control. After the women had consumed their assigned liquid, researchers used ultrasound to measure how well their brachial artery (the primary artery supplying blood to the arm) relaxed and expanded after a blood pressure cuff that had been inflated for 5 minutes on participants’ forearms was deflated – a challenge test called “flow-mediated dilation.”

Flow-mediated dilation gives a functional “video clip,” showing how well blood vessels are able to respond to a sudden increase in blood flow, and is often used to help determine an individual’s risk for heart disease.

Black tea significantly improved flow-mediated dilation compared with water, but adding milk completely blunted tea’s beneficial effects.

To confirm these findings, similar experiments were performed in laboratory studies using isolated rat blood vessels and endothelial (blood vessel lining) cells. Once again, while tea increased the activity of the enzyme in endothelial cells that promotes relaxation (endothelial nitric oxide synthase) and promoted blood vessel dilation, these beneficial effects were completely inhibited when cow’s milk was added to the tea.

Why does cow’s milk short-circuit tea’s cardio-protective effects? Casein proteins found in cow’s milk bind to the helpful catechins in tea, preventing them from doing their protective work.

Practical Tip: To reap tea’s protective effects against cardiovascular disease, enjoy your tea au naturel or, if you love “milk tea,” try substituting a little soy milk or rice milk for cow’s milk.

Reference:

Lorenz M, Jochmann N, von Krosigk A, Martus P, Baumann G, Stangl K, Stangl V. Addition of milk prevents vascular protective effects of tea. Eur Heart J. 2007 Jan;28(2):219-23. Epub 2007 Jan 9.

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Technorati Tags: tea, cows milk, heart, alternative medicine, complimentary medicine, health and wellness

Posted by: Joe Pizzorno, Jr., ND at 9:15 am