Marc Joseph Nutrition - Blog

There’s quite a bit of research that suggests calorie restriction (CR), as long as essential nutrient needs are met, may help to significantly reduce disease risk and improve longevity. There are even organizations focused solely on the topic.

Researchers at the University of California and Children’s Hospital Oakland Research Institute note in a paper in the 2007 Annual Review of Nutrition that even reducing calorie intake later in life may lead to beneficial effects (e.g., preventing or slowing the growth of cancer).

The article mentioning the paper discusses some of the possible ways CR may work:

Physiological changes associated with aging include cell damage and the emergence of cancer cells. The most important effects of low calorie diets and longevity therapeutics given late in life may not be to prevent this damage, but instead to stimulate the body to eliminate damaged cells that may become cancerous, and to stimulate repair in damaged cells like neurons and heart cells. Low calorie diets drive the body to replace and repair damaged cells. This process usually slows down as we age, but low calorie diets make the body re-synthesize and turn over more cells - a situation associated with youth and good health. Dr. Spindler and his colleagues used their screening method to search for drugs which cause pre-cancerous and cancerous cells to commit suicide and to replace those cells with new, healthy cells. It is thought that the body does this because it normally kills some cells like damaged and rogue cancer cells to provide energy when it is starving. Then it replaces these cells when a meal is eaten.

A more detailed overview of the potential biochemical mechanisms behind CR’s beneficial health effects can be found in this March 2006 Scientific American article:

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Garlic is a plant with many potential medicinal benefits, including:

• Cardiovascular effects
• • Reduction of mildly elevated cholesterol and triglyceride levels
  • Decreased oxidation of LDL cholesterol (antioxidant)
  • Improved arterial elasticity
  • Reduced platelet stickiness & increased fibrinolytic (anti-clotting) activity
• Anti-microbial actions
• • Anti-bacterial/yeast/viral
• Anti-cancer effects
• • Reduced risk for developing several types of cancer, including colon, stomach, & esophageal

However, as this recent paper notes, for best results it’s important to:

1. Crush the garlic and allow it to sit for a few minutes before adding it to a cooked dish. With crushing, alliin, the sulfur-containing amino acid in garlic, comes in contact with the enzyme alliinase, which converts alliin to allicin. Allicin and related sulfur compounds (thiosulfinates) are believed to be the primary compounds responsible for garlic’s healthy effects.
2. Only cook the garlic for a brief period of time at moderate heat or lower once it’s added to the dish. The paper’s authors noted that garlic’s anti-platelet strength was preserved in both crushed and uncrushed garlic samples when they were cooked at under 400 degrees F for less than 3 minutes. Whereas cooking for 6 minutes reduced the anti-platelet effect in the crushed garlic and completely suppressed it in the uncrushed sample. Cooking for 10 minutes completely inhibited the anti-platelet effect in both samples.

Garlic prepared and eaten as above is preferred. Garlic supplements with standardized allicin content are an ok second choice. However, since a garlicky taste* can sometimes even be noticed with deodorized supplements, and supplements likely can’t replicate all of the potentially beneficial compounds found in raw garlic, this is a case where I’d definitely go with the food.

* Parsley eaten with or after a meal can help to blunt garlic odor.

Regular and moderate garlic intake (e.g., 1 to 2 cloves per day) may be a useful part of an overall program for maintaining a healthy heart.

Note: Because of garlic’s anti-clotting effects, people taking anticoagulant (blood-thinning) drugs, such as Coumadin or aspirin, should work with their physician or nutritionist to determine if garlic use is safe and appropriate.

In a recent study, Italian researchers found that southern Europeans consuming the highest amounts of onions and garlic had a significant reduction in risk for many cancers.

Listed below in parentheses are the percent declines in cancer risk that researchers found for high onion and garlic consumption, respectively:

• Oral cavity & pharynx (84%, 39%)
• Esophageal (88%, 57%)
• Colorectal (56%, 26%)
• Laryngeal (83%, 44%)
• Breast (25%, 10%)
• Ovarian (73%, 22%)
• Prostate (71%, 19%)
• Kidney (38%, 31%)

The results are consistent with other studies that have found beneficial effects for these vegetables in helping to prevent cancers of the digestive tract, prostate, and breast.

Garlic and onions are both members of the allium vegetable family. Organosulfur compounds found in these vegetables are believed to help prevent cancer development by:

• Promoting metabolism of carcinogens by promoting Phase II and slowing Phase I detoxification pathways in the liver.
• Enhancing cellular production of glutathione, the body’s primary and most important antioxidant.
• Arresting unregulated cell growth, which is seen with cancer, and promoting apoptosis (normal programmed cell death).
• Inhibiting microbial growth (yeast, bacteria, viruses), which may be involved in cancer development.

So, mangia! Grab the (xylitol-sweetened) breath mints and get going…

Earlier this month, I wrote a post about the potential of curcumin, the yellow pigment found in tumeric, a common ingredient in curry, to protect against cognitive decline and slow the development of Alzheimer’s disease (AD).

A recent study reaffirms curcumin’s anti-inflammatory properties and found that it significantly reduced inflammation in rats with rheumatoid arthritis. As the study abstract notes:

Turmeric has been used for centuries in Ayurvedic medicine as a treatment for inflammatory disorders including arthritis. On the basis of this traditional usage, dietary supplements containing turmeric rhizome and turmeric extracts are also being used in the western world for arthritis treatment and prevention.

To-date, this study has been one of the few in-vivo (in animal or people) studies performed using curcumin.

It’s believed that curcumin inhibits the NF-KappaB inflammation pathway, which acts as the innate immune system’s master-switch. However, the authors of this study, as well as the authors of this review of curcumin’s effects, mention the NF-kappaB inflammatory pathway may be just one of many that curcumin helps to control:

Modern science has revealed that curcumin mediates its effects by modulation of several important molecular targets, including transcription factors (e.g., NF-kappaB, AP-1, Egr-1, beta-catenin, and PPAR-gamma), enzymes (e.g., COX2, 5-LOX, iNOS, and hemeoxygenase-1), cell cycle proteins (e.g., cyclin D1 and p21), cytokines (e.g., TNF, IL-1, IL-6, and chemokines), receptors (e.g., EGFR and HER2), and cell surface adhesion molecules.

Hopefully we’ll see some controlled intervention human studies in the future to provide even better evidence of curcumin’s effects in inflammatory diseases such as rheumatoid arthritis, as well as in other diseases with significant inflammatory components, such as inflammatory bowel disease, asthma, Alzheimer’s disease, and even cancer.