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Part II Nutrition Assessment, Consequences, and Implications

TABLE 17.5 Vitamin K Significant Dietary Sources (50 μg Or More Vitamin K/100 g) Category

Sources Fats and oils Canola (rapeseed) oil, soybean oil

Additional Information

Exposure to fluorescent and sunlight rapidly destroys vitamin K in oils.

Vegetables

Highest sources: seaweed (extremely high levels), cooked spinach, collard greens, mustard greens, kale, turnip greens; raw forms of these vegetables are lower in vitamin K per equal measure.

Other sources: asparagus, bran, broccoli, brussels sprouts, beet greens, cabbage (green raw), chayote leaf, chickpeas (garbanzo beans), chive (raw), coriander leaf, cucumber peel, endive, green tomato, lettuce, lentils, mint, mung beans, nettle leaves, purslane, romaine lettuce, scallions (green onions), beans, soybeans, swiss chard, watercress

Fruits Spices Meat and fish Other

Strawberries, apples with green peel, kiwifruit, blueberries, prunes, grapes

Parsley, basil, cilantro, sage oregano, black pepper

Pasture-raised chicken, grass-fed beef, grass-fed lamb, shrimp, sardines, tuna, salmon

Beef liver, chicken liver, pork liver, egg yolk, green tea leaves, algae (purple laver and hijiki)

be tailored to a person’s genetic makeup.” Pharmaco- genomics may play an important role in identifying responders and nonresponders to medications, avoiding adverse events, and optimizing drug dose. Drug label- ing may contain information on genomic biomarkers (26).

Drugs do not work the same way for everyone. How individuals respond to drugs for the treatment of cancer or other illnesses differs based on the activity and function of enzymes in the body. It can be difficult to predict who will benefit from a medication, who will not respond at all, and who will experience adverse drug reactions. With this new science, researchers are learning how “inherited differences in genes affect the body’s response to medications. These genetic differ- ences will be used to predict whether a medication will be effective for a particular person and help prevent adverse drug reactions” (26).

In the future, genomic information will be utilized to predict and manage the large interindividual differ- ences in response to drug and nutrient intakes. Recent

advances in human genomics have uncovered exten- sive variations in genes affecting nutrient metabolism, but their full impact on nutrient requirements remains to be clarified. Differences in the rates of absorption, distribution, uptake, utilization, biotransformation, and excretion ultimately impact the concentration of a nutrient at a target site. Variations in genes that code for target proteins such as receptors, enzymes, trans- porters, or ion channels can also impact the response to a nutrient. The goal of pharmacogenetics is to use genetics to predict response to therapy and to tailor medications appropriately. Further research is needed in the role of human genetic variation in nutrient metabolism.

The Phase I Enzymes

The vast majority of phase I reactions are catalyzed by the cytochrome P450 (CYP) superfamily of hemopro- teins, which includes numerous isoforms with their own distinct nomenclature system (27). A large quantity of P450 is found in the human liver. The P450 enzyme

Higher concentrations of vitamin K are found in the outer leaves and peels of vegetables.