Optimizing Diet

With numerous factors contributing to a decreased nutrient content of our food supply, it is critically important to choose a nutritious diet full of fruits and vegetables, nuts, fish and legumes.

I know it is hard to fit fruits and vegetables into your diet. These foods often take more time to prepare and spoil quickly. In a survey of almost 2,000 adults, the most important values for choosing lunch were convenience and taste. Health was the least important factor. Most of us are busy juggling work, family and other activities, but convenience foods tend to be higher in fat, refined carbohydrates and sodium. Furthermore, these foods usually involve extensive processing to enhance taste, which can destroy or remove nutrients. Furthermore, higher amounts of these types of foods are associated with marginal micronutrient intake and low serum concentrations of vitamin A, E, C, B12, folate and carotenoids.

Low fruit and vegetable intake is sixth on WHO's list of 20 risk factors for mortality worldwide and the NHANES examination survey indicates that only 40% of Americans eat the recommended five or more servings of fruits and vegetables per day. Most Americans have significantly lower intakes of vitamins A, C and E, and magnesium than the estimated average requirements. This is likely because the standard American diet is typically characterized by a high intake of saturated fat, red meat, refined grains and sugar rather than an emphasis on fruits and vegetables.

Fruits and vegetables are rich in vitamins, minerals and fiber. Diets rich in fruits and vegetables have been associated with a decreased risk of many chronic diseases, including heart disease, stroke, high blood pressure, diabetes and some cancers. Research has also found that replacing high calorie foods with lower calorie foods, such as fruits and vegetables, can be an important part of an effective weight management plan. Fruits and vegetables also provide potassium and magnesium, which are precursors of bicarbonate, helping to neutralize diet-induced acid load and calcium excretion. It has been theorized that diets higher in protein and lower in potassium and magnesium could result in a low-grade metabolic acidosis that in turn could induce bone demineralization and osteoporosis.

Fruits and vegetables, particularly brightly colored fruits and vegetables, are also rich in phytonutrients. It is estimated that plant foods contain more than 10,000 phytonutrients, including carotenoids like beta-carotene, lycopene and lutein, flavonoids like quercetin and catechins, ellagic acid and resveratrol. These compounds give foods their characteristic color and smell, meaning that brightly colored fruits and vegetables typically contain more. In the body, these compounds function as antioxidants, help reduce inflammation and in some cases may help reduce the risk of cancer.

Optimally, you should include a fruit and/or a vegetable every time you eat a meal or snack:

• Chop raw vegetables and sauté with an egg for breakfast
• Make egg-vegetable quiche muffins and store in the freezer for a quick nutritious breakfast
• Add fresh berries to your cereal or oatmeal
• Make a smoothie with fruit, vegetables yogurt, and juice (especially helpful for using up overly ripe produce)
• Choose a piece of fresh fruit or cut-up vegetables for a snack
• Use a dried fruit mix for an on-the-go snack
• Add cut veggies to mixed greens for a healthy salad
• Mix fruit into yogurt
• Make a stir-fry with broccoli, carrots, mushrooms, snap peas, or other vegetables
• Use chopped or pureed vegetables (such as carrots or spinach) in pasta sauces or lasagna
• Grill vegetable kabobs or roast a pan of vegetables
• Leave fruits and vegetables (such as cherry tomatoes, apples or grapes) out in a bowl where they will be easily accessible and noticed

Ensuring adequate essential fat intake is another critical dietary factor. The standard American diet is generally low in omega-3 essential fatty acids, which are important for healthy cardiovascular function, inflammatory balance and cognitive support. Reports estimate that Americans typically consume a diet that has a ratio of 10:1 omega-6 to omega-3 fatty acids. Research indicates that the optimal ratio, reflecting what our ancestors ate, is closer to 3:1. Choosing foods with omega-3 essential fatty acids is important.

Optimal sources of essential fats include:

• Omega-3 fatty acids: fish, grass-fed meats and dairy products, flaxseed, soybeans and walnuts
• Omega-6 fatty acids: vegetable oils, grains and seeds

Optimally, you should include a source of omega-3 fatty acids at least once per day:

• Snack on walnuts or other nuts (¼ cup of walnuts contains about 2.7 grams omega-3 fatty acids)
• Add flaxseeds to baked goods and smoothies (¼ cup of flaxseeds contains about 6.3 grams)
• If you choose to eat meat, place an emphasis on fish and grass-fed meat and poultry (4 ounces of salmon or sardines contain about 1.3 grams, 4 ounces grass-fed beef contains about 0.1 gram)
• Make legumes a centerpiece of your diet (1 cup kidney beans contains 0.2 grams, 1 cup soybeans contains 0.6 grams)
• Use olive oil on salads and other raw foods (an ounce of olive oil contains about 0.1 grams)

Optimizing Nutrition when Purchasing Foods

Ideally produce should be grown locally, organically and eaten shortly after harvest. What does this mean for the average consumer?

First, home gardens can be wonderful way to get in touch with the food supply and demonstrate to children where our food comes from. Your local garden store can help, provide organic fertilizers and even plant seedlings. Composting your food scraps will help limit your trash production, as well as make a rich fertilizer for your garden. Gardens provide the freshest tastiest food for your plate.

Second, farmer's markets are a close second to raising food yourselves. Farmer's markets provide fresh locally raised crops and sometimes, grass-fed meats. To find your nearest farmer's market, check out the website: http://www.localharvest.org/ Look for farmer's that are certified organic or use integrated pest management rather than pesticides. Not all small farmer's will choose to become certified organic but many still use alternative methods to prevent pests that will result in healthier foods.

Lastly, look for local organic produce and grass-fed meats in your grocery store. Often the country of origin will be marked on the food item. Ask the produce manager what they have that is local. Choose organic to limit exposure to pesticides (remember organically raised produce had a 30% decrease in pesticides compared to conventionally raised produce). Choose fresh non-wilted produce. In general, the conditions that result in wilting are the same as those that cause nutrient losses. Avoid irradiated crops, which can decrease vitamin C up to 95% depending on the crop.

Optimize Nutrition When Preparing Food

Next, make sure you eat these foods! We often have the best of intentions to cook good produce, but it often ends up crushed and wilted on the bottom of the refrigerator before you can actually eat it. Estimates suggest that more than 20 pounds of food per person are wasted every month in the U.S., translating to $936 for each household in a year. Another article states that “food waste has progressively increased by ~50% since 1974 reaching more than 1400 kcal per person per day”. This is a huge drain on our water and energy resources, translating to more than one quarter of the total freshwater consumption and approximately 300 million barrels of oil per year. Finding quick healthy meals to prepare for yourself and your family can help ensure that your best intentions do not go to waste.

While it is better to purchase whole vegetables and chop in your kitchen rather than purchasing precut mixes in bags (chopping accelerates nutrient losses), if you find that purchasing the pre-cut mixes increases the amount that you eat and prevents you from wasting food, then by all means go ahead. Additionally, use the humidity settings in your refrigerator to keep fruits at 85-95% relative humidity and vegetables at 90-98%.

It is important to pay attention to the way in which you prepare foods to prevent excessive nutrient losses. Cooking can destroy certain vitamins, such as vitamin C, but generally leaves minerals unharmed. In an experiment involving potatoes, cooking decreased the vitamin C content by 30%. For this reason it is important to eat both cooked and uncooked fruits and vegetables. It is also important to eat food as quickly as possible after cooking. In the same potato experiment, keeping the potatoes warm for 1 hour after cooking decreased the vitamin C by an additional 10%.

Choose cooking methods that use small amounts of water and avoid long exposure to high temperatures. Starches, fiber and amino acids can break down when foods are heated above 100 degrees or exposed to prolonged periods of heat or alkali, while cooking foods in large amounts of water can leach minerals, vitamins and amino acids out of foods. Some studies suggest microwaving may be the best method of preserving nutrients, however steaming or stir-frying would also be good choices. In a comparison of cooking methods, vitamin C and iron retention was significantly higher in four of the five vegetables tested when cooked by microwave-steaming and stir-frying with oil compared to boiling or stir-frying with water. In another experiment, the highest losses of vitamin C occurred in water blanched spinach, compared to blanching with steam or microwave.

Eat a variety of raw and cooked vegetables daily since nutrients can be increased or decreased with cooking. Tomatoes have been shown to lose 30-60% of quercetin during boiling, however
can gain anywhere from 44-64% during baking or cooking as tomato sauce. Squash, peas and leeks can lose up to 40% of their phytonutrients during cooking, while peppers, green beans and spinach increased in phenolic compounds with cooking. Broccoli increased by 16% after steaming or microwaving but lost 6% during boiling. Don't get bogged down in the details of these studies, but make sure to include 1-2 servings of fruits and vegetables per meal and choose different foods regularly to ensure a variety of important phenolic compounds in your diet.

Lastly, chill foods that will not be eaten right away to minimize nutrient losses. Storing cooked foods for long periods of time will decrease the nutrient content, just like losses during storage and transport. It is better to chill foods that will not be eaten and heat them up when you are ready to eat them.