Thursday, May 23, 2013

How to Preserve Nutrients in Cooking

Raw or cooked vegetables? Microwaved or steamed? Does it make a difference? Actually, the method of cooking does affect different types of vegetables in both a positive and negative way. For example, when cooking tomatoes, the bioavailablity of Lycopene (a carotenoid with antioxidant properties) is increased; however, the amount of Vitamin C decreases.

There is a lot of debating going on over microwaving vs. using a conventional oven. Some say microwaving is the devil because of nutrient loss and cancer causing properties. Some nutrients are broken down when they are exposed to heat. So, is microwaving better than cooking vegetables in a convention oven? Since both use heat to cook, and microwaving takes a shorter amount of time to cook food, it is a slightly better option than cooking in the oven.

Frying is probably one of the worst ways to cook your vegetables. The heat is so high that almost all nutrients are immediately destroyed.  Frying also causes the release of free radicals, which are detrimental to your health.

Boiling is probably the second worst way to cook your vegetables, unless you plan on using the remaining broth. When you boil vegetables, all the nutrients leak out into the water. Since many people do not save the water from the vegetables, you are not getting the benefits of the cancer fighting properties they hold.

Steaming is the gold standard for cooking vegetables. Steaming helps to retain the nutritional value of your vegetables. Some key things to remember when steaming are: don't use too much water (1/2 cup is usually good) and don't overcook (5-7 minutes is usually good for most vegetables).

Raw Food 
Just to clarify, I am only speaking about eating certain foods raw, like vegetables, not the raw food diet, where a person will only eat raw foods (no meats, fish, etc). Studies have shown that both raw and cooked vegetable consumption are inversely related to epithelial cancers, lung cancer, and breast cancer; however, these relationships may be stronger for raw vegetables than cooked vegetables.

Degradation of Vitamins & Minerals
Once vegetables are picked, their vitamin and mineral content begin to degrade. To slow this process, most vegetables should be refrigerated until they are used.  Also, many vitamins are easily destroyed by oxygen. In order to minimize nutrient loss, cut vegetables should be stored in airtight containers in the refrigerator. Just to keep in mind, after about 24 hours in the fridge, cooked vegetables will lose 1/4 of their Vitamin C content. Vitamin C is the most likely vitamin to be lost in cooking. It is very sensitive to heat, air, and water. To minimize nutrient loss, cook in as little water as possible.

The bottom line is, whether you are eating your vegetables raw or cooked, at least you are consuming vegetables!

Monday, May 20, 2013

Fun Fruit and Vegetable Facts

Did you know that banana trees are not trees? The banana plant is actually a giant herb. Today's blog features fun facts about different fruits and vegetables!

-One avocado tree can produce up to 400 avocados a year! 
-Avocados are a good source of Vitamin C, potassium, magnesium, folate, and fiber. They are also high in Vitamin E.

-Ever wonder how many seeds were on your strawberry? On average, there are 200!
-Strawberries are not truly a berry, despite their name. 
-Strawberries are a good source Vitamin C, potassium, and fiber.

-Kiwi can be used as a meat tenderizer. Cut the fruit in half, rub over meat, and leave for 10-15 minutes. 
-The brown fuzzy skin is edible!
-Kiwi are a good source of Vitamin C and E, potassium, and fiber.

-Native to North America. They were deemed the name "cranberry" because the flowers resemble cranes.

-The name broccoli comes from the Latin word brachium, which means "branch" or "arm"
-Broccoli is a good source of Vitamin A, folate, iron, calcium, and fiber.
-Ounce for ounce, Broccoli has more vitamin C than an orange and as much calcium as a glass of milk.

-The nectarine is actually a subspecies of peach that lacks the gene for fuzz. 

-Cabbage needs to be kept cold in order to retain its Vitamin C.

-Pick carrots that are dark orange in color (more beta-carotene).
-Carrots are a good source of fiber, beta-carotene, and Vitamin A.

-They are technically a fruit; however, they are prepared and eaten like vegetables.
-The French used to refer to the tomato as the "apple of love."
-Tomatoes are a good source of Vitamin A and C. 

-Ever wonder why apples float? They are good for apple bobbing games because they are 25% air!

-You can speed up the ripening of a pineapple by standing it upside down (on the leafy end).

EXTRA Food Facts
-In ancient Greece and Rome, fava beans were used in voting; a white bean was used to cast a yes vote, and a black bean for no
-Pinch your nose and eat an onion, apple, and potato. They will all taste sweet. The difference in flavor is caused by their smell.

Thursday, May 9, 2013

Monounsaturated Vs. Polyunsaturated Fats

In my last blog, Saturated Fat Vs. Trans Fat, I talked about the unhealthy fats in our diet. As I stated before, you need fat in your diet! Fat is necessary for brain development, insulation, cushion of organs, and absorption of fat-soluble vitamins (Vitamins A, E, D, K).

The two main healthy fats are monounsaturated (MUFAs) and polyunsaturated fats (PUFAS).  MUFAs and PUFAs are found in a variety of foods and oils and are typically liquid at room temperature. Studies have shown that eating foods rich in MUFAs and PUFAs improve blood cholesterol levels, decrease your risk of heart disease, and benefit insulin levels and blood sugar control (helpful for Type 2 Diabetes).

Polyunsaturated fats are further broken down into two categories: omega-6 and omega-3 fatty acids. Omega-6 and omega-3 are essential fats because our bodies need them but cannot make them. Omega-6 and omega-3 EFAs are important for brain function and normal growth and development.

Humans evolved on a diet with a ratio of omega-6 to omega-3 essential fatty acids (EFA) of 1 to 1. In the typically Western diet, the ratio of omega-6 to omega-3 EFAs is about 15 to 1. This excessive consumption of omega-6 EFAs has lead to the promotion of cardiovascular disease, cancer, and inflammatory diseases. Studies have shown that an increase of omega-3 EFAs will suppress these negative effects. Omega-3s have also been found to decrease the risk of coronary artery disease, lower blood pressure, decrease triglyceride levels, reduce blood clotting, reduce symptoms of depression, protect against memory loss, ease arthritis, and boost immunity.

Food Sources of Monounsaturated Fats
-Olive, canola, peanut, sesame, and sunflower oils
-Peanut butter
-Nuts and seeds

Food Sources of Polyunsaturated Fats
-Corn, safflower, soy, nut, and cottonseed oils
-Nuts and seeds
-Fatty fish (trout, herring, salmon, tuna) (Omega-3s)
-Flaxseeds (Omega-3s)

The American Heart Association recommends eating fish at least 2 times per week. If you are unable to consume enough omega-3 EFAs from your diet, you should consider a fish-oil supplement. In general, aim for a supplement between 500 and 3,000mg of EPA/DHA. For maximum absorption, take your supplement with food.

Recipes and Cooking Ideas
-Sauté onions with eggs and avocado.
-Substitue flax seed oil for another cooking oil.
-Try a slice of avocado on a sandwich or make guacamole.
-Substitute ground nuts in place of breadcrumbs.
-See my peanut butter ball recipe for a way to incorporate flax seed in your diet!


Monday, May 6, 2013

Saturated Fat Vs. Trans Fat

Fats have certainly gotten a bad rap in the past few years. The new health craze has pushed for even more low-fat products.  But then again, some fats are good. This back and forth on fat sure makes it hard for consumers to know what to eat. Yes, you do need fat in your diet. It is essential for hormones, insulation, and protection of your organs from damage. The truth is that you do not need as much fat as you think. Also, the quality of the fat you eat is important. I am just going to focus on the two major harmful fats, Trans fat and Saturated fat. The healthy fats, Monounsaturated and Polyunsaturated, will be covered later. 

What Are Saturated Fats?
Saturated fats are mainly found in animal products and are typically solid at room temperature. Their chemical makeup consists of carbon atoms that are saturated with hydrogen atoms (hence the name "saturated" fat). The American Heart Association recommends limiting your intake of saturated fats to less than 7% of total calories. If you are consuming a 2,000 calorie per day diet, your intake of saturated fat would be less than 16 grams. 

Where Do You Find Saturated Fats in Foods?
Saturated fats occur naturally in many foods. Some examples include fatty beef, pork, and poultry with skin. Saturated fat is also found in butter, cheese, ice cream, and other dairy products made from whole or 2% milk. Many baked and fried foods contain high levels of saturated fats. 

Why Are Saturated Fats Harmful?
Saturated fat raises total blood cholesterol and LDL (bad) cholesterol levels. This increases your risk of heart disease and stroke. Studies have shown that saturated fat may also increase your risk of developing type 2 diabetes. 

What Are Trans Fats?
Trans fats are made during food processing through the partial hydrogenation of unsaturated fats. Hydrogenation basically means that hydrogen atoms are added to the carbon atoms. This process creates a product that is less likely to spoil, which increases the shelf-life of many foods. The American Heart Association recommends limiting your trans fat intake to less than 1% of your total calories. If you are consuming a 2,000 calorie per day diet, your intake of trans fat would be less than 2 grams. 

Where Do You Find Trans Fats?
Trans fat is found mainly in processed foods. Examples include cookies, crackers, cakes, some stick margarines, fried foods (donuts, French fries), chips, candy, and frozen dinners. When reading nutrition labels, look for the words "partially hydrogenated" in the ingredient list. Any oil that is partially hydrogenated is a trans fat. Be aware of the "0 Trans Fat" products. The FDA allows that phrase to be on any product with .5 grams of trans fat per serving. Since many people do not stick to serving sizes, they may be consuming more trans fat than they think. 

Why Are Trans Fats Harmful?
Trans fats raises your LDL (bad) cholesterol and lowers your HDL (good) cholesterol, a double whammy! Trans fats increase your risk of developing heart disease and stroke. Trans fat also increases blood triglyceride levels, which leads to hardening of the arteries (atherosclerosis). Studies have also shown that trans fat increases inflammation by damaging the cells lining your blood vessels. 

Tips for Lowering Saturated and Trans Fat
1. Eat a balanced diet rich in fruits and vegetables (no trans/saturated fat!).
2. Choose leaner cuts of meat and trim visible fat before cooking.
3. Remove the skin from chicken, turkey, and other poultry.
4. Drink low-fat or skim milk rather than whole or 2%. You will still be getting the same amount of calcium.
6. Decrease your intake of fast food. Many fast food restaurants still use partially hydrogenated oils for frying. 
7. Consume monounsaturated fat (olive oil) and polyunsaturated fat (soybean, sunflower oil).

Remember, not all fat is bad. You need fat in your diet! Also, be aware of the low-fat products. These so-called-healthy products simply swap saturated and trans fat for sugar. When in doubt, it is better to opt for a little fat over a lot of sugar.