jueves, 23 de enero de 2014

Superfoods broadcast's script

Today we are talking about super-foods. You've probably heard that certain foods have special properties to promote health and to stave off chronic diseases such as cancer or heart disease, boost immunity or fight against ageing process. But what qualities need a food to be considered as super?

First of all I must say that there isn't such a thing as a superfood; we should use instead the term "healthy choice". There isn't even a legal or scientific definition of superfood. In my opinion marketing is taking advantage of the motivation that consumers have to buy products which provide health and wellness. That's why we continually hear of new superfoods popping out in the market. We all want to believe that eating this kind of foods will give our bodies the health kick we need to ward off illness and ageing, and we think that if we eat that food once, twice or even three times a day we can forget about the rest of the diet. However, this can have an unwanted outcome; for example, you may eat a lot of nuts or olive oil a day because they have fats that protect your heart, but they are so fattening that may provide you with all the calories you need a day making you overweight, so instead of making you healthier they are having the opposite effect. It also does not make sense to me to eat berries frequently to prevent cancer or ageing so you don't have to make the effort of stopping smoking, do more exercise or have a plant-based healthy diet.
This is the reason why, instead of eating super foods, we should focus on having a super diet based on a variety of nutritious foods, including plenty of fruits, vegetables, whole grains, legumes, nuts, seeds or other foods dense in nutrients; and we should limit the intake of saturated or trans fats, as well as salt, sugar, and we have to try to achieve and maintain a healthy weight and do exercise regularly. This is the only way to reach an optimal health. So we have to keep in mind that a single food, no matter how "ultra-healthy" it is, it’s not a magic bullet that makes up for a crappy diet.

Lately I’m reading a lot about the properties that flavonoids have. Why are they so important?

Eating high levels of flavonoids, including anthocyanins and other compounds (found in berries, tea, and cocoa) are associated with lower insulin resistance and better blood glucose regulation. Findings published last tuesday in the Journal of Nutrition reveal that high intakes of flavonoids could offer protection from type 2 diabetes.

Another study also found that these food groups lower inflammation which, when chronic, is associated with diabetes, obesity, cardiovascular disease, and cancer.

What are the most popular superfoods?

They change from time to time, but currently the most “trendy” foods that we think that superpower our diet are fruits, especially berries like blueberries or citrus fruits like oranges, lemons or pomegranate, which can lower blood pressure in the short-term, as well as reduce the oxidative stress. Vegetables as broccoli, pumpkin, tomatoes, and dark leafy vegetables like spinach or kale; tree nuts as walnuts, foods rich in omega-3 fatty acids such as salmon; foods rich in fiber capable of lowering the cholesterol levels such as the one found in oats and beans; soy because of its isoflavones; and of course, probiotic foods like yogurts.

Does really dark chocolate have healthy properties or it’s just an excuse invented by somebody with a sweet tooth who doesn’t want to have any regrets after eating it?

I’m also the kind of person who uses the excuse of the healthy benefits of some foods to eat them as much as I want… But jokes apart, it is true that dark chocolate have a high amount of antioxidants known as flavonoids which can lower blood pressure by increasing the elasticity of the blood vessels, so it helps to protect your heart. But not all chocolates do the trick, it must have over a 60% of cocoa content, so the darker, the better; and in addition it will have a lower amount of fat and sugar.

Most of the superfoods are characterised for being rich in antioxidants. Why are they so important?

There are highly reactive toxic free radicals that we create as part as normal metabolism, like oxygen free radicals because, although we need to breathe oxygen to live, it produces metabolic byproducts which are very harmful. Our body produces some types of antioxidants to block these free radicals, but it cannot make some antioxidants which are essential for us, that's why we need to eat them with the food, for instance: vitamins C and E. There are other compounds which are also antioxidants that our body cannot produce like beta-carotene, lycopene and lutein, which we get from plant-foods. And there is a large class called polyphenols that include flavonoids found in green tea, red wine or dark chocolate. There are thousands of these compounds in our diet, and you can't get all the antioxidants you need in a single food, that's why we need to eat a variety of foods.

The foods that contain the highest amount of antioxidants are fruits like berries. Blueberries are the most popular among the berries because they are packed with anthocyanins, which have the property of inhibiting the growth of cancerous human colon cells, as well as kill them off. Other antioxidants found in blueberries can prevent and reverse age-related diseases like cancer, diabetes, and heart disease.

I’m thinking of drinking more tea to get more antioxidants, which tea would you recommend to me?

I would recommend green tea because although in overall it has the same amount of antioxidants than the black tea, green tea have a specially powerful antioxidant known as ECGC. There have been more than 100 studies focusing on this natural substance and its anti-cancer benefits.

I would also like to mention the white tea because like black and green tea, it is also derived from Camellia sinensis, thus, it shares many of the same chemical properties and health effects of tea. This tea contains the most antioxidants because it retains a higher amount of catechins, which are a group of polyphenol antioxidants present in fresh tea leave and due to the process the white tea is made, it’s the tea with the highest amount of these substances which have been found to reduce cholesterol, decrease blood pressure, and improve the function of blood vessels, thereby decreasing the risk of cardiovascular disease.

I usually add beetroot to my salads because I’ve heard it’s good for your heart. Is it also due to the antioxidants?

It’s true that beetroot is an ally of your heart, but for a different reason. It contains high levels of nitrate which is converted by the body into nitric oxide which can lower blood pressure and also reduce the blood clotting.

After the foods rich in antioxidants, the superfoods more popular are those that can lower the cholesterol. But do they really work?

According to an important study publicated in 2003 in “The journal of the American Medical Association” a diet that include soy fiber, protein from oats and barley, almonds and margarine from plant sterols lowers the cholesterol levels as much as statins, the most widely prescribed cholesterol medicine.

But these nutrients have other additional health benefits. For example, fiber has the bonus of reducing the risk of cancer, it slows down the absorption of sugar and helps to manage your weight by making you feel full sooner and longer.

I use soy sauce very frequently in my cooking, can it also help to reduce my cholesterol?

I’m afraid that soy sauce doesn’t count, you should eat tofu, soy milk or edamame to do the trick.

Is it true that drinking red wine offer protection against heart disease?

Red wine has been associated with numerous health benefits, including a lower rate of heart disease. Studies have shown that drinking small to moderate amounts of red wine daily (which is from 1 to 3 standard drinks) may help protect middle-aged and older adults against heart disease. However, before you uncork that bottle of red wine, remember that alcohol is addictive. Heavy drinking can lead to high blood pressure, heart disease, stroke, obesity and liver failure.
Due to the harmful health and social consequences of alcohol consumption, adults who do not drink alcoholic beverages should not start even though there are some potential heart health benefits.

What is the scientific evidence behind the media's superfood claims?

Although there are many studies that have shown that certain foods have health-promoting properties, most of those results can not be applied to real diets. For example, they tend to use very high concentrations of those nutrients, what is not realistically attainable in the context of a normal diet. On top of that, the physiological effects of many of these foods are often short-term. So if you want to get the benefits they have, you should consume them in huge amounts. And this could be counter-productive for certain foods such as red wine because of its alcohol or cocoa in the form of dark chocolate which would boost intake of not only their healthy flavonoids but also of other nutrients that we should limit in our diet like sugar or saturated fats.

Another problem with the studies about superfoods is that they are done mainly on animals like rats, or in vitro with human cell cultures, and there is no guarantee that these nutrients will have the same effects in people when consumed in a normal diet where we combine nutrients, which can modify the absorption of certain compounds. For instance, the beta-carotene in carrots and spinach, is more readily absorbed when eaten together with a source of fat such as olive oil or any other salad dressing.

What is the truth behind the publicity of the Superfoods?

There are some foods which have a better nutrient profile than others, but we have to remember that what really counts is how we eat them on the context of our diet. So if you eat them several times a day but then you fill the rest of your diet with fast food or pre-cooked food you are not going to prevent any disease.

Sometimes the media publicite processed products as superfoods, but I wouldn't put a fortified potato chips in the superfoods list because it should be always a real unprocessed food. Another example would be the bread made from enriched wheat flour publicized as a whole grain. But actually It’s the germ and bran of the whole grain you’re after because it’s in there where you can find all the nutrients a grain product has to offer, like magnesium, chromium or folate, And when you purchase processed grains like bread made from enriched wheat flour, you don’t get these.

Can you give us another example of a superfood which claims are false or misleading?

I would like to make a warning about the açaí scams. There are several companies that sell açaí supplements as part of a multi-level marketing scheme. Marketers of these products make unfounded claims. They state that açaí and its antioxidant qualities provide a variety of health benefits, none of which has scientific confirmation to date. False claims include reversal of diabetes and other chronic illnesses, as well as expanding size of the penis and increasing men´s sexual virility. But the truth is that it has less content in polyphenols and lower antioxidant potency if we compare it with others 11 varieties of frozen juice pulp, scoring even lower than strawberries, grapes, mango or acerola.

I see superfoods are not as miraculous as we think, but can they be harmful?
Some people shouldn’t have too much of certain superfoods. For example people who have a family history of breast cancer shouldn’t consume extra soy because of its estrogenic effect. There are other people who are more vulnerable to the toxic effect of alcohol, so they shouldn’t drink red wine regardless how good it seems to be.

But the real problem with the promotion of the superfoods is that they can be misleading in the sense that they can distract you from the true message that is to have a diverse and balanced diet.

If you could only add to your diet one kind of superfood which one would you choose?

I would probably choose a food with anti-inflammatory properties like blueberries or a food high in omega-3 fatty acids; as inflammation is a key driver of all chronic diseases.

Blueberries have this quality because they are packed with potent antioxidants and bioflavonoids, and moreover they also have a high content in vitamin C and potassium. So their benefits go beyond their capacity of lowering your risk of heart disease.

And you can find the omega-3 fatty acids in wild cold-water fish such as salmon, sardines, herring, mackerel or other fatty fish. They can help to ease inflammatory diseases like arthritis as well as reduce the risk of cardiovascular disease, and recent studies show evidence that they can also help with memory loss and Alzheimer's disease and reduce depression as well.

I’d also like to point out that omega-3 fatty acids are essential for the developing brain and vision, so pregnant and breastfeeding women should take these supplements. But if you're pregnant avoid the fish liver oils like cod liver oil, because its high concentration in vitamin A can harm your baby, so choose fish oil instead, and don’t eat fish high in mercury such as shark, swordfish, tilefish and king mackerel.
My favourite source of omega-3 fatty acids is salmon. But stay away from the breaded and deep fried variety… they don’t count in your goal of 6-9 ounces of fish per week.

These healthy fatty acids are not exclusive to fish, they can also be found in vegetarian sources such as seaweed, flaxseeds, walnuts and fortified eggs.

What is the final thought you want us to keep in mind?

We should increase the intake of superfoods, but without forgetting the rest of the diet and to keep an overall healthy lifestyle. The only way we can take advantage of the health properties of the superfoods is when we replace not so healthy choices by these foods. For example, for a double health whammy, replace sugary sodas with tea, or choose nuts as a snack instead of potato chips.

In conclusion, when it comes to ensuring a balanced nutrient intake of good health, we need to increase the range of nutritious foods as opposed to focusing on a diet based solely on one or a handful of foods claimed to be "super". Importantly, this should include a greater quantity and variety of fruits and vegetables.

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