Cooking certain vegetables is thought to kill the enzymes they contain, a process that makes them easier to digest, but which can result in vitamin loss. Vitamin loss in food is affected by:
- Exposure to air
- Exposure to light
- Exposure to heat
- Whether a vitamin is fat- or water-soluble - Vitamin loss from cooking is more significant with water-soluble vitamins such as B and C, because prolonged heating breaks them down. By contrast, fat-soluble vitamins (D, E, A and K) as well as fat-soluble plant chemicals (e.g. lycopene) become more concentrated with cooking; the vegetable loses water content, thereby decreasing dilution of the nutrients.
To optimize vitamin levels in your vegetables:
- Use foods when optimally fresh.
- If cooking, use steaming over boiling, and avoid long cooking times.
- Remember that the significance of losing some of a vegetable’s vitamins/nutrients depends on the food’s context in your overall diet. If you’re eating plenty of fresh produce, the benefits lost by cooking a single dish are unlikely to make a dent in your health.
- A balanced diet should include all nutrients, both fat and water-soluble.
- A raw food diet may not be practical if you have digestive issues. As we get older, some of us have digestive problems with raw onions, cucumbers, bell peppers etc. At this point it becomes subjective. How much benefit are we deriving from eating all raw foods if we don't enjoy how it makes us feel? The nutrients gained may be outweighed by the discomfort.
- 12 ounces trimmed raw broccoli, cut in 1-inch lengths (including floret section)
- 12 ounces peeled daikon, cut in 1-inch lengths
- For dressing:
- 2 Tablespoons unseasoned rice wine vinegar
- 1 Tablespoon ponzu soy sauce
- 1 Tablespoon Dijon mustard
- 1 Tablespoon chopped garlic
- 1 Tablespoon sushi ginger
- 1 Tablespoon white or yellow miso
- 2 teaspoons toasted sesame oil
- 1/4 cup canola oil
- 2 Tablespoon chopped cilantro
- 1/2 teaspoon crushed red pepper flakes (optional)
- Garnish: 1 teaspoon black sesame seeds (or toasted white sesame seeds)
At the end of the day, I think it's best to eat a combination of fresh cooked and raw foods to achieve the optimal amount of nutrients and vitamins they contain. Here's a scrumptious raw recipe for a vegetable we typically enjoy cooked.
Ginger Sesame Broccoli Daikon Salad
Yield: Eight (8) 3/4-cup servings
Using the grating attachment (not fine) of the food processor, grate the broccoli and daikon in bowl of the food processor. Transfer to a medium mixing bowl. Set aside.
Rinse bowl of food processor to reuse. In bowl of food processor, measure vinegar, soy, mustard, garlic, ginger and miso. Process til smooth. With blade running, drizzle in sesame oil and then canola in a thin stream to create an emulsified dressing. There will be about 1/2 cup. Add cilantro and chili flakes (if using) to vegetables. Pour dressing over and toss well. Garnish with sesame. Makes about 6 cups.
Calories 100, Calories from Fat 70, Total Fat g 8, Sat Fat g < 1, Cholesterol mg 0, Sodium mg 160, Total Carb g 5, Dietary Fiber g 2, Sugar g 2, Protein g 2, Vitamin A % 10, Vitamin C % 70, Calcium % 4, Iron % 4