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Wednesday, December 29, 2010

Eat the Whole Orange


As a conscious omnivore, when I eat meat, I eat as much of the animal as possible.

I like to treat fruits and vegetables the same way.

I save scraps like leek tops and shiitake stems for soup stock. I buy beets with their greens attached and eat those too. I roast the seeds from squash and pumpkins. And I always eat the outer layer of fruits and vegetables whenever possible because they are most nutritious with their skins and peels intact.

Antioxidants, which protect plants from the sun's ultraviolet radiation, are concentrated in the outer layer of fruits and vegetables. Produce peels and skins are also good sources of fiber, minerals and other important phytonutrients.

Citrus fruits have exceptional peels. They contain flavonoids like nobiletin and tangeritin that have anti-inflammatory and anti-tumor effects in the body. Studies show that these flavonoids can induce the death of cancer cells (apoptosis) and reduce the chance that tumors will spread to other parts of the body.

Limonene, a monoterpene compound found in the essential oils of citrus fruit peels, also has anti-cancer activity. It stimulates enzymes in the liver that break down carcinogens and alters gene expression in cancer cells to inhibit their growth. Monoterpenes like limonene have been shown to prevent cancers of the breast, colon, liver, lung, pancreas and skin.

Because pesticides are often concentrated on the outer layer of produce, only eat peels from citrus fruits that have not been sprayed. When your citrus fruits are organic, always eat their zest.

Citrus fruits are easy to find in the winter and several varieties abound: grapefruits, oranges, blood oranges, tangerines, clementines, mandarins, satsumas, lemons, limes, kumquats, etc. When you buy by the bag, prices for organic fruit can be comparable to their conventional counterparts.

How can you eat citrus zest?
  • Stir it into yogurt and smoothies
  • Sprinkle it on top of oatmeal and granola
  • Whisk it into vinaigrettes and sauces
  • Grate it into soup or risotto
  • Dry it and add it to loose leaf teas, seasoning blends, and dry rubs
  • Make a citrus reduction that you can drizzle over yogurt or whisk into vinaigrette (recipe follows)


Blood Orange Reduction

Make extra of this reduction if you can because it's lovely to have some leftover in the fridge. I like to stir it into cooked steel cut oats and add a dollop of plain whole milk Greek yogurt. (To make steel cut oats, bring 1 part rinsed oats and 3 parts water to a boil, turn off heat, cover, allow to sit overnight, then cook on the stove top over low heat for 10 minutes or until thickened as desired.)

If you can't find organic blood oranges, use another variety.

2 organic blood oranges, zest and juice
Zest of 2 organic lemons (save the juice for another purpose)
Pinch sea salt

Add all the ingredients to a small saucepan and warm over medium heat. Once the mixture starts to simmer, turn the heat down to low. Swirl occasionally and allow it to reduce until it becomes a few spoonfuls of a thick sauce. Taste for seasoning and adjust if necessary. Cool completely and store in an airtight container.


Blood Orange Balsamic Vinaigrette

This recipe is the perfect amount for a big salad. If you want to have some leftover, double or triple the batch.

1 tbsp blood orange reduction
1 tbsp balsamic vinegar
3 tbsp extra virgin olive oil, first cold pressing
Ground peppercorn to taste
Pinch sea salt (optional)

Whisk all ingredients together until smooth. Use immediately or store in an air-tight container in the fridge.

References:

Rooprai HK et al. Evaluation of the effects of swainsonine, captopril, tangeretin and nobiletin on the biological behaviour of brain tumour cells in vitro. Neuropathology and Applied Neurobiology. 2001 Feb;27(1):29-39.

Crowell PL, et al. Human Metabolism of the Experimental Cancer Therapeutic Agent D-Limonene. Cancer, Chemotherapy and Pharmacology, 1994;35:31-37.

Crowell PL and Gould MN. Chemoprevention and Therapy of Cancer by d-Limonene. Critical Reviews in Oncogenesis, 1994;5(1):1-22.

Dietary Phytochemical Research Demonstrates Potential for Major Role in Cancer Prevention. Primary Care & Cancer, 1996;16(7):6-7.

Foods That May Prevent Breast Cancer: Studies Are Investigating Soybeans, Whole Wheat and Green Tea Among Others. Primary Care and Cancer, February 1994;14(2):10-11.
 
Haag JD et al. Limonene-Induced Regression of Mammary Carcinomas. Cancer Research, 1992;52:4021-4026.

Hensrud DD and Heimburger, DC. Diet, Nutrients, and Gastrointestinal Cancer. Gastroenterology Clinics of North America, June, 1998;27(2):325-346.

Lee YC et al. Nobiletin, a citrus flavonoid, suppresses invasion and migration involving FAK/PI3K/Akt and small GTPase signals in human gastric adenocarcinoma AGS cells. Molecular and Cellular Biochemistry. 2011 Jan;347(1-2):103-15. Epub 2010 Oct 21.

Leonardi T et al. Apigenin and naringenin suppress colon carcinogenesis through the aberrant crypt stage in azoxymethane-treated rats. Experimental Biology and Medicine (Maywood). 2010 Jun;235(6):710-7.

Orange Peel Oil Studied as Cancer-Fighting Agent. Medical Tribune, May 30, 1991;11.

Potter JD. Your Mother Was Right: Eat Your Vegetables. Asia Pacific Journal of Clinical Nutrition, 2000;9(Suppl.):S10-S12.

Schardt D. Phytochemicals: Plants Against Cancer. Nutrition Action Health Letter, April 1994;21(3):7-13.

Stavric B. Role of Chemopreventers in Human Diet. Clinical Biochemistry, 1994;27(5):319-332.

Steinmetz K and Potter JD. Vegetables, Fruit and Cancer II: Mechanisms. Cancer Causes and Control, 1991;2:427-442.

Steinmetz KA and Potter JD. Vegetables, Fruit, and Cancer Prevention: A Review. Journal of the American Dietetic Association, 1996;96:1027-1039.

Wednesday, December 22, 2010

Is Calcium Dangerous?

An article published earlier this year in the British Medical Journal concluded that taking calcium supplements is associated with an increased risk of having a heart attack.

However, there were several problems with this study. Among them:
  • It was a meta-analysis, a study of studies, but the studies selected excluded several trials that linked calcium supplements to a reduced risk of heart attack. 
  • Vitamin D helps our bodies absorb calcium, but the study excluded people who took calcium in combination with vitamin D.
  • According to the researchers, the increase in heart attacks was only "modest" and there was no increase in the number of deaths from heart attacks.
This isn't the first poorly designed trial to grab headlines while misleading and confusing the public, but it raised an important issue. Too many people take too much calcium.

Of course our bodies need calcium. Most of it is used to strengthen bones and teeth, but calcium has other important functions. It stabilizes cell membranes and aids the transport of compounds into and out of cells. Calcium regulates neurotransmitters, substances that transmit nerve impulses, and helps initiate blood clotting. And without calcium, muscles, including the heart, don't contract properly.

Bone Metabolism

Putting more calcium into your body doesn't necessarily mean putting more calcium into your bones. Bones are constantly remodeling themselves and this complex process is controlled by a complex system of hormones. It is not controlled by the amount of calcium you take in (although calcium must be present in the blood before it can be incorporated into bone matrix).

Many factors are involved in bone mass: bone cell growth, bone cell destruction, mineralization (adding more minerals like calcium to bone matrix) and resorption (removal of minerals like calcium from bone matrix).

In childhood, when bone cell growth exceeds bone cell destruction, our bones and our bodies become bigger. Once we're fully grown, bone growth balances bone destruction. After the age of 30, bone destruction slowly begins to exceed bone growth and we gradually lose bone mass as we age. After 50, declining levels of estrogen and testosterone can speed the process.

At any age, exercise can slow or even reverse bone loss. Simply put, our bones stay strong when we stay active. Weight-bearing exercises and activities that place forces on bones stimulate growth, ensuring that the body will be able to withstand future forces. When we become sedentary and forces that stimulate bone growth no longer exist, we lose bone mass. 

Osteoporosis

The number one reason that people take calcium supplements is to prevent bone loss and osteoporosis. But for most older people, osteoporosis is not a disease at all. It's a natural aging process.

The real danger is not weak bones. Falls and fractures have a much greater impact on quality of life. Only 1 in 4 elderly individuals who sustain such injuries are able to return to their pre-fracture activity level. 75 percent of older adults who survive falls require specialized long-term care in a rehabilitation facility or nursing home, and 25 percent die within one year.

Regular exercise not only keeps bones strong, it also improves balance and coordination, making falls and fractures less likely. Studies have shown that walking at least 2 hours each week can reduce the risk of hip fractures in elderly adults. For best results, I recommend participating in a variety of activities that apply forces to a variety of bones.  People who do not exercise regularly should talk to their doctor before they start.

To further reduce the risk of falls and fractures, older adults should live in clutter-free environments with good lighting, have their sight and hearing tested annually, wear rubber-soled shoes and use caution when walking on slippery or uneven surfaces.

Calcium Supplements

Getting enough calcium is important but more isn't necessarily better. Worldwide population studies have shown that people who consume the most calcium – like those in Scandinavian countries and the United States – also have the highest rates of fracture, while people who consume the least – like those in Asian and Mediterranean cultures – have the lowest fracture rates.

Ideally, calcium should come from our diet.  When it doesn't, it must be supplemented. Our bodies probably need about 1000 mg of calcium each day. But before you start taking supplements, evaluate your diet and estimate your true needs.

Each day, the average person usually consumes at least 300 mg of calcium from foods that are not especially rich in calcium. So assume a starting point of 300 mg and add what you get from these calcium-rich foods:
  • 1 cup of cooked spinach = 300 mg of calcium
  • 1 serving of dairy (1 cup of milk or yogurt, or 1.5 ounces of cheese) = 300 mg of calcium
  • 3 ounces of fish with soft bones that you eat like canned wild salmon and sardines = 400 mg of calcium
  • 1 cup of cooked collard or turnip greens = 400 mg calcium
Adults who eat, on average, at least one daily serving of dairy, dark green leafy vegetables or fish (with bones) already get 600 mg of calcium from food alone. So they only need to supplement 400 mg per day.

Adults who eat at least three servings of these foods have no need to supplement calcium at all. This is a good goal.

Calcium supplements come in many forms. Calcium carbonate is inexpensive to produce and widely available, but it is more difficult to digest and can cause constipation. Larger doses are required because a lower percentage is absorbed.

Better choices include calcium citrate, calcium malate and calcium aspartate. These forms are more costly to produce and take up more space inside capsules and tablets, but they are better tolerated and more easily digested and absorbed by the body.

Those who do take calcium supplements should supplement an equal amount magnesium. Get magnesium from foods too. Good sources include tofu, cherries, figs, beans and lentils, halibut, dark green leafy vegetables like Swiss chard and beet greens, and nuts like almonds and cashews.

Vitamins D and K are necessary for the absorption and utilization of calcium. Vitamin K should not be taken in supplement form unless your doctor recommends it, but you should include food forms in your diet. Turnip greens and broccoli are by far the best source of vitamin K, but other green leafy vegetables, cabbage, liver and green tea are also good sources. Make sure to eat these foods with some form of fat to ensure that the vitamin is well-absorbed. Vitamin K plays an important role in blood clotting, so individuals taking blood-thinning medications should get specific dietary recommendations from their doctor.

Sunlight stimulates the skin to produce vitamin D - which is why deficiencies are most common in winter and in areas furthest from the equator - but vitamin D can also be found in food. Good sources include cod liver oil, fish (especially sardines, which are also a good source of calcium when consumed with the bones), mushrooms, egg yolk, lamb and beef.

Vitamin D can also be found in supplements. Because it is fat-soluble, vitamin D should always be taken with food or fish oil.

However, taking too much vitamin D in supplement form can cause it to accumulate in the body and reach toxic levels. Small amounts are usually not worrisome, but larger amounts (1,000 IU per day or more) should only be taken if blood tests show that levels are low. If you aren't sure, ask your doctor for the test. It's worthwhile because low levels of vitamin D have been linked to an increased risk of osteoporosis, autoimmune disease, depression, heart disease and cancer.

Remember that supplements are no substitute for a healthy diet and that calcium output is as important as calcium intake. Excessive consumption of coffee or alcohol, and diets high in sodium, animal protein and grains can cause the kidneys to increase excretion of calcium. But plant-based diets high in vegetables and fruits and low in sodium additives cause the kidneys to increase calcium retention. It's a great reason to eat plenty of dark leafy greens and avoid processed foods.

References:

Bolland MJ et al. Effect of calcium supplements on risk of myocardial infarction and cardiovascular events: meta-analysis. BMJ. 2010 Jul 29;341:c3691. doi: 10.1136/bmj.c3691.

Feskanich D et al. Walking and Leisure-Time Activity and Risk of Hip Fracture in Postmenopausal Women. Journal of the American Medical Association. 2002;288(18):2300-2306. doi: 10.1001/jama.288.18.2300

Koot VC et al. Functional results after treatment of hip fracture: a multicentre, prospective study in 215 patients. The European Journal of Surgery. 2000 Jun;166(6):480-5.

Friday, December 10, 2010

Aspirin Against Cancer?

Aspirin recently made headlines as an anti-cancer drug.

In a new study, researchers followed more than 25,000 people who took aspirin regularly for five years. They concluded that taking aspirin daily was associated with a 21% reduced risk of cancer.

This does make some sense.

Aspirin is an anti-inflammatory drug, and inflammation has a strong association with cancer. Inflammatory mediators stimulate cell division and inhibit cell death, prompting tumors to get bigger. Inflammation also triggers tumors to release vascular endothelial growth factor (VEGF), a protein that stimulates the growth of new blood vessels needed to fuel tumor growth and spread malignant cells throughout the body.

Researchers at the Glascow Hospital in Scotland have also linked inflammation to cancer survival. They found that cancer patients with the lowest levels of inflammation lived longer and those with the highest levels of inflammation had the worst prognosis.

Aspirin may reduce inflammation, and reducing inflammation may reduce the risk of cancer, but aspirin isn't the best strategy for cancer prevention. Common side effects include nausea, vomiting and heartburn, especially when taken long term. But more serious and life-threatening adverse reactions can occur, like hepatitis (inflammation of the liver) and internal bleeding.

A Better Strategy

Eating an anti-inflammatory diet and leading an anti-inflammatory lifestyle is a healthy way to prevent cancer and reduce the risk of other chronic illness like cardiovascular disease, diabetes and obesity.

An anti-inflammatory diet is rich in antioxidants and omega-3 fatty acids found in:
  • Vegetables and fruit 
  • Raw nuts and seeds
  • Nontoxic seafood like wild salmon, Pacific halibut, herring, sardines and anchovies
  • Meat, eggs and dairy products from animals raised on pasture and never exposed to pesticides, antibiotics or hormones
To follow an anti-inflammatory diet, it is important to avoid trans-fats, simple carbohydrates and omega-6 fatty acids found in:
  • Flour and foods made from flour
  • Sugar, sugar substitutes, corn syrup, agave nectar and sweet foods and beverages
  • White rice
  • Meat, eggs and dairy products from animals fed grains (even if those grains are organic)
  • Industrial fats like corn, soybean, sunflower, safflower, canola oils and vegetable oils
An anti-inflammatory lifestyle involves avoiding exposure to toxic and carcinogenic chemicals. Regular exercise is also important because it has anti-inflammatory effects in the body and it helps improve cardiovascular and musculoskeletal fitness, balance, coordination, mood and sleep.

Fish Oil

If you seeking a supplement to provide anti-inflammatory and anti-cancer effects, consider fish oil.

Like aspirin, fish oil reduces inflammation in the body and prevents cells from getting too sticky and forming clots. But unlike aspirin, fish oil is safe for long term use and does not compromise the gastrointestinal lining. Individuals who are allergic to fish and those who take blood-thinning medications should seek individualized recommendations from their doctor before taking fish oil.

Purity is important because toxic contaminants like heavy metals and industrial pollutants are stored in animal fat, i.e. oils from fish. Look for a reputable brand that can provide proof of purity from an independent lab. I like Nordic Naturals because their fish oils are pure and they use only sustainably harvested fish to make their products.

Reference:

Rothwell PM et al. Effect of daily aspirin on long-term risk of death due to cancer: analysis of individual patient data from randomised trials. The Lancet, Early Online Publication, 7 December 2010.  doi:10.1016/S0140-6736(10)62110-1

Wednesday, December 1, 2010

Safe Alternatives to Toxic Household Products

Last month I wrote about toxic and carcinogenic ingredients in best selling brands of common household products.

This week I share my top twelve ways to protect yourself and your family, as well as my recipe for making your own Non-Toxic All-Purpose Cleaner.

  • The Household Product Labeling Act is currently being reviewed by the US Senate. Contact your senators and urge them to require product labeling that protects consumers and the environment, not manufacturers.
  • Use cookware made of cast iron, stainless steel, copper, glass or ceramic. Avoid non-stick cookware.
  • Avoid food and beverages that have been in plastic containers or metal cans. Use stainless steel or glass water bottles.
  • Look for fragrance-free household and personal products and remember that labels like "green,” "organic" and "natural" are not legally defined.
  • Research personal products on the Environmental Working Group's Skin Deep Cosmetics Safety Database. Search by product, ingredient or company to read safety reviews and make good choices when selecting items like soap, shampoo, toothpaste, deodorant, contact lens cleaner, make-up, nail polish, sunscreen, hair care and baby products.
  • If your air is malodorous, open some windows and circulate the air. As an alternative to air fresheners, use essential oil diffusers with 100% pure essential oils. Avoid perfume oils.
  • Use essential oils also for cleaning. They are anti-bacterial and can be used in solution to clean kitchen and bathroom surfaces (see recipe below). Tea tree essential oil is especially effective at removing mold and mildew.
  • Use baking soda as an abrasive agent to remove residue and stains from glass, ceramic, stainless steel and silver. Add a few drops of water to make a baking soda paste for cleaning the stove, sink, counters, toilet and tub. You can also use baking soda paste as an alternative to toothpaste.
  • To keep drains free of blockages, flush them with boiling water on a weekly basis. To unclog drains, first pour ½ cup of baking soda down the drain, then pour in 1 cups of white vinegar. Wait for foaming to reside, then flush with plenty of boiling hot water.
  • Use olive oil to polish wood furniture. Mix 3 parts of an inexpensive olive oil (not extra virgin) with 1 part freshly squeezed lemon juice. Apply it with a soft cloth, rub briskly and allow the area to air dry. (You may want to test a small area before you apply it to an entire piece of furniture.) The solution is only good for one day, so mix up just enough for your immediate needs and discard what you don’t use.
  • Coarse salt can be used to scour cookware. To remove rust stains, sprinkle salt over the area, squeeze fresh lemon juice on top and allow it to sit for several hours before you wipe it off.
  • Use white vinegar to wash windows and floors, polish mirrors, and soften laundry (add one half cup to the rinse cycle in place of store-bought fabric softener). White vinegar is the base for my Non-Toxic All-Purpose Cleaner below, which can be used on counters, sinks, stove tops, appliances and tiles.

Dr. Sarah's Non-Toxic All-Purpose Cleaner

1 cup white vinegar
5 drops tea tree essential oil
5 drops lavender or orange essential oil
½ cup water (optional)

Add all the ingredients to a new, clean spray bottle. Label the container with the ingredients and date. Store it out of the reach of children.

To use, shake the bottle gently to incorporate any essential oils that may have separated. Spray the cleaner on dirty surfaces and wipe off with a clean wet sponge. For tougher cleaning jobs, omit the water and leave the solution a few minutes longer before wiping it off. Do not use this cleaner on wooden or delicate surfaces.