We all know that the old saying that “you are what you eat”. As nutrition research advances, this becomes even more evident. For example, there is emerging evidence in the field that what a pregnant woman eats during pregnancy can influence not only her unborn fetus, but even successive generations! Quite amazing really!
Recent studies have shown that maternal nutrition can influence patterns of gene expression, by a mechanism known as epigenetic modification in the sperm cells on fetal mice that can be passed along to successive generations. These are actual modifications to DNA that influence gene expression which are inheritable. Does the same occur in humans? Probably, but further research is required.
Emerging science also is providing evidence that the maternal diet prior to conception may be equally important. So, does this concept only apply to women? Absolutely not. Again, recent studies have suggested that paternal nutrition can influence genetic events in sperm cells that could be passed along to successive generation.
In sum, these emerging areas of nutrition research have expanded the realm of healthy eating from beyond the individual to a person’s “bloodline”. The new slogan might then be, “you are what your mother and father (and grandparents) ate”! So, eat healthy! Not only for you own sake, but for others on down the family tree.
Ah, Halloween. Trick-or-treating, candy, ghosts and goblins and too many empty calories! Don’t get me wrong, it’s a fabulous holiday that all kids and young-at-heart adults love. But given the explosive rise in childhood obesity and increases in the incidence of type 2 diabetes among adolescent, we should collectively be concerned. Here are some ideas on how to lessen the nutritional impact of this fun holiday.
1) Limit daily consumption of candy as much as possible. A child may have only 100 kcals of discretionary calories available each day to maintain proper body weight. More kcals from junk foods, and weight and adiposity rise over time.
2) Buy your candy a day or two before the holiday. This way, no one is tempted to have a sugar hog fest and you might save money as these items typically go on sale as the day approaches.
3) Have dinner before going trick-or-treating. This one is for rather obvious reasons…less likelihood of snacking on the candy as one goes door-to-door.
4) Have an active evening. Take a longer walk to enjoy the decorations and burn some calories while you’re at it.
5) Practice portion control and know which ones are the healthier choices. Limit the amount that children can eat each day and don’t necessarily trust them to do this on their own. Placing the stash out of their reach or where you can control it is best.
So, have a happy Halloween and stay healthy!
Nutrition knowledge is great, but how does one translate this to the grocery store or local corner market. A few tips from someone who has scoured the shelves of many grocery stores over the past several years in search of healthier choices.
1) Don’t get fooled by the cover! Food manufacturers are out to make a profit, not necessarily promote your health. Statements made on the front of the package can be misleading. So, refer to the Nutrition Facts panel and the ingredient list. This information is factual. This then leads me to point 2.
2) Learn how to read nutrition facts panels and ingredient lists. The ingredient list goes from the most abundant component to the least abundant (based upon weight). So, if you are looking for a whole-grain product. The first ingredient should be something like “whole wheat flour” or “whole oats”.
3) What to pay attention on the Nutrition Facts Panel. First, check serving size. To compare products on the store shelves, make sure serving sizes are the same. This is another trick that food manufacturers like to use. Next, look for fat content and type of fats present. Avoid foods with saturated fats and absolutely avoid foods with trans-fats. Lower cholesterol is also better. Next, check sodium and fiber content. Higher fiber is good and high sodium is bad. Total carbohydrate and sugar content can be misleading as you can’t tell if it contains added, refined sugars (which are bad) or naturally occurring sugars (which are better).
4) Learn different “buzz” words for added sugars and true whole grain products. There are numerous types of added sugars, which are a nutritional dead end. A few examples, all meaning added, refined sugars: brown sugar, corn sweetener, corn syrup, dextrose, fructose, fruit juice concentrate, glucose, high-fructose corn syrup, honey, invert sugar, lactose, maltose, molasses, raw sugar, sucrose, syrup and table sugar. And…there are more! Overwhelming, huh? Same goes for whole grain products. Look for these terms at the beginning of the ingredient list: whole grain, whole wheat, whole (other grain), stoneground whole (grain), brown rice, oats, and oatmeal. Again, food manufacturers will trick you with words and labels regarding whole-grain products.
5) Remember, “free” does not necessarily mean zero. For example, if a food contains less than 0.5 g of trans-fat per serving, it can be labeled “trans-fat free”. Thus, you want to avoid foods that have partially hydrogenated oils in the ingredient list (even if they are labeled “trans-fat free”). Again, educate yourself and read food labels!
6) Look toward the end of the ingredient list where you typically find preservatives listed. Avoid meat products with nitrates and nitrites as these may increase risk for canner, in particular colon cancer. Other ingredients are also listed here, such as dyes and other additives. If you don’t know what something is, you should exercise caution and do a little research.
In summary, nutrition knowledge does one little good without also having the knowledge to decode food labels, Nutrition Facts Panels and ingredient lists. Having both sets of knowledge will prepare you to withstand the onslaught of manufacturer tricks and ploys used to get you to but their products. If you focus on whole, natural foods, you are in good shape, but we all will need other prepackaged products on the store shelves. This is where we need to educate ourselves and make wise choices. Happy shopping!
Dietary supplements are a multi-billion dollar industry in the United States. Surprisingly, however, supplement manufacturing is not regulated by the Food and Drug Administration, which oversees foods consumed by humans and various drugs used to treat a variety of disease. You might ask yourself then, who does regulate the supplement industry? Great question! It turns out that the individual manufacturers are responsible for the safety of the products they produce and sell. Sounds pretty scary, if you ask me. What then happens if a particular supplement is associated with adverse reactions in users? The FDA then steps in at this point and essentially does an investigation. In some cases, the FDA may issue a recall of the supplement. What happens next? Another excellent question. This is exactly what was considered by the authors of a recent study published in the Journal of the American Medical Association (Medical News Today Article). The JAMA study involved an examination of products that were recalled by the FDA from US markets for being composed of ingredients that could have serious adverse health consequences, even leading to death. It turns out that almost 50% of FDA recalled class 1 drugs since 2004 have been for dietary supplements. The authors of the JAMA paper note that many of the banned substances were still commercially available 6 months or more after the FDA recall. The study authors obtained the recalled supplements and did thorough chemical analyses (using fancy scientific techniques such as gas chromatography and mass spectrometry). What they found is actually quite disturbing! One or more pharmaceutical adulterant (i.e. a potentially toxic or banned substance) was found in two-thirds of the recalled products that remained for sale on store shelves. This included 11 of 13 supplements for sports enhancement, 6 of 9 for weight loss, 1 of 5 for sexual enhancement, and 13 of 20 which were produced by American Manufacturers. In many cases the substance that originally led to the FDA recall remained in the product and in other cases, other adulterants were found. So, what does this mean for me and you? Among us, perhaps 50% take some kind of dietary supplements. If this is you, the best advice is to be very careful. This article outlines some of the unexpected hazards with these products. One way to protect yourself is to look for the US Pharmacopeia Verified Mark. This ensures that the products with this seal have undergone independent testing. Another alternative is to obtain all the nutrients and other dietary products you need from whole natural foods, an approach that many with scientific knowledge of nutrition have taken.
As most of you know, there are numerous weight-loss plans out there, and most of them have been shown to be ineffective. But, what if you could eat Twinkies and other items usually considered to be “junk” foods and lose weight and improve overall health? That’s a diet plan that many could stick to. Sounds great, huh? That’s exactly what a Kansas State University Professor did recently (Professor Haub’s Diet Experiments) as a proof-of-concept exercise that suggests that cutting calories is all that matters for healthy weight loss. This is certainly open for debate, but let’s take a closer look at the so-called Twinkie diet and the results of his own personal experimentation.
Professor Haub reduced his calorie intake by 800 kcals per day (from 2600 to 1800) and consumed 60% of calories from junk food (i.e. convenience store foods such as Twinkies, Little Debbies and other snack cakes). He also consumed a protein shake, a multivitamin, a can of green beans and four stalks of celery daily. During his 2 month experiments, he avoided meat, whole-grains and fruits. He also maintained his moderate-intensity exercise regime throughout the experimentation period. What were the results of this quite interesting experiment? You might be surprised! He lost 27 pounds and reduced his BMI from almost 29 to about 25. His percent body fat dropped from 33.4 to 24.9 and his ‘bad’ cholesterol (LDL) decreased by 20% while his ‘good’ cholesterol (HDL) increased by 20% (The Twinkie Diet: Caution, Toxic).
Most nutrition experts and clinicians would agree that these short-term change in physiologic parameters are positive, but let’s take a critical look at this approach to weight loss and some claims made by Dr. Haub.
1) Calorie reduction is required for weight loss. What foods you consume in the short-term during this calorie reduction phase are not critical. What matters is what happens when you later achieve energy balance after weight loss is completed. Could you maintain health then with a focus on junk foods?
2) Temporary changes in biomarkers should be interpreted with caution. What matters is whether these changes are stainable for longer periods of time. Changes that he noted in blood cholesterol levels would be protective against heart disease, but only if maintained for a period of months or years.
3) Vitamins and shakes should not be substituted for real, healthy foods. Most nutrition scientists would agree with this contention. Healthy whole foods have health promoting properties that supplements and shakes cannot match.
4) These foods that he consumed are nutrition train wrecks, which almost certainly cause harm over the long term. Incredibly, Twinkies contain 39 ingredients, many of them unpronounceable and of questionable relevance to human nutrition.
The bottom line is that for weight loss, calories should be reduced while still maintaining nutritional balance. This cannot be achieved when the focus is on convenience store “Franken foods”. The basic nutritional guidelines should be followed, while simultaneously increasing energy expenditure. If Dr. Haub had maintained his junk food habit over a long period of time, he would almost certainly compromise his health. What will be your approach? Twinkies and Little Debbies, or natural whole foods with proven health-promoting properties. You know that’s best, after all its common sense!
Most people enjoy cooking outdoors on the grill during the warm summer months. This activity appeals to the prototypical human omnivore as well as to others with more restrictive dietary approaches. Many foods are great grilled, from steak to poultry to fish and veggies. Have you ever considered how grilling foods may alter the nutrient content of the cooked foods? How about when certain foods become black and charred from direct contact with open flames or high temperatures? How does this affect the health benefits of foods we typically cook on the grill? Great questions! Let’s take a closer look at these issues.
Many years ago, scientists discovered that meats (in particular red meat and chicken) cooked at very high temperature over open flames formed heterocyclic amines (HCAs) and aromatic hydrocarbons. It turns out that these chemical compounds have toxic and potential mutagenic effects when consumed by humans. Animal studies also confirmed that both compounds are carcinogenic (i.e. cancer-causing). Moreover, observational studies have linked higher intake of these compounds with increased incidence of colorectal cancer in humans. Sounds quite scary, especially for those home grill masters. The good news, however, is that you can take precautionary steps to decrease the production of these compounds and still enjoy grilled foods.
Here are some tips to make grilled meats healthier (and some alternatives to grilling).
1) Grill vegetables or seafood. These foods typically produce much less of these toxic compounds.
2) Marinate meats prior to grilling. What you use to marinate the meat and how long seem to not matter.
3) Microwave food before cooking and pour off the juices. 1-2 minutes in the microwave significantly reduces HCA levels.
4) Flip foods frequently. Doing so every 1-2 minutes keeps the surface temperature lower and reduces the production of HCAs.
5) Keep grilled foods moist. Drier and more well done foods produce more HCAs and other toxic compounds. This may explain why grilled hot dogs and sausages form less HCAs, since they are encased with an outer layer which prevents the meat from drying out during cooking.
6) Don’t eat the drippings from grilled meat and poultry, as HCAs and other toxic compounds may be more concentrated here that in the meat itself.
7) Consider alternative cooking methods. The cooking methods that produce the most to least HCAs: grilling and barbecuing (most), broiling and pan-frying (still on the higher side), baking, roasting and stir-frying (less) and boiling, steaming, poaching or stewing, and microwaving (least).
The Bottom Line: Enjoyed grilled foods, but keeping these guidelines in mind will lead to a healthier experience that can be just as tasty as the old “burn it to a crisp” method.
Did you know that there are more bacteria in your intestine than there are cells in your body? Unbelievable, right? Moreover, it turns out that these bugs actually contribute to health and disease. This is a hot topic in the scientific world and it turns out that a lot of nutrition scientists are quite interested in this area of research. What then, you might ask, is the link between nutrition and gut bacteria (or the so-called ‘gut microbiota’), and how exactly do they influence one’s health and well-being? Great questions! Let’s explore these concepts.
In a healthy person, most nutrients are digested and absorbed in the small intestine. This includes mono-and disaccharides (i.e. simple sugars), amino acids derived from dietary proteins and fats. Complex carbohydrates, such as soluble and insoluble fibers and resistant starches, however, cannot be digested by human enzymes and enter the large intestine (or colon) intact. This also happens to be where the bulk of bacteria reside. Interestingly, the gut microbes can then digest soluble fibers and resistant starches in the colon. Some of the breakdown products of these complex carbohydrates, called short-chain fatty acids (for example, butyrate), provide fuel for the cells lining the colon (as well as providing fuel for the bacteria that digest them). These dietary constituents have been termed ‘prebiotics’ as they feed the gut microbes. The amount of fiber in your diet can actually alter the composition of the gut microbiota, by promoting the growth of certain types of bacteria.
There are literally dozens of different bacterial species in the human intestine, some are beneficial to us and others can be harmful under certain conditions. It turns out that changes in the composition of the gut microbiota can increase the risk for: functional bowel disorders, inflammatory bowel diseases, celiac disease, food allergies, type 2 diabetes, obesity, autism and even depression (Science Daily Article).
So, consumption of prebiotics is one way to positively influence the gut microbiota. Are there others? Yes, probiotics. Probiotics are living bacteria that can be found added to certain foods in the grocery store. The probiotic bacteria added to these foods populate the gut with good bacteria and, in principle at least, outcompete the bad bacteria, tipping the balance towards health. Probiotics have been suggested to improve resolution of diarrhea, prevent and treat urinary tract infections, treat irritable bowel syndrome, reduce bladder cancer recurrences, and prevent or reduce the severity of colds and flu (amongst other purported benefits).
So then, are you kind to your intestinal co-inhabitants by feeding them nutritious snacks (i.e. complex carbohydrates)? Or are you, like most Americans, not consuming enough fiber in your diet. How about probiotics? Do you consume foods with beneficial live bacteria? They are available at your local grocery store right now. If you answered no to these questions, you might want to think about this issue. It could positively influence your health in ways that we currently understand and in other ways that will undoubtedly be discovered in the future.
Food labels have long had to list all ingredients on the Nutrition Facts Panel. This is great, if you can interpret the many additives found in most processed foods (which now total over 3000!). Consider, for example, titanium dioxide (used as a coloring agent), butylated hydroxytoluene (used as an antioxidant), or propylene glycol alginate (used as a food thickener or stabilizer). Scary, huh? But at least these products are listed on the label, by law. What about foods that have been altered at the genetic level (called genetically modified organisms [GMOs])? Do they require special labeling? Do you think they should, and if so, why?
First, let’s take a look at the science and rational behind the genetic manipulation of agriculturally important organisms. GMOs are plants or animals that have been genetically modified to contain DNA from microorganisms, such as bacteria of viruses, or other plants or animals. These experimental combinations of genetic material could not have been otherwise produced naturally. Almost all GMOs have been engineered to withstand herbicides or to produce insecticides. The idea is that if the plant produces a protein that allows it to withstand a particular herbicide (e.g. Roundup), then the farmer just sprays the whole field and everything dies except the engineered crop plant. Although the scientists and the companies they work for have declared GMOs to be safe for human consumption, there are others that disagree (see, for example, NON GMO Project).
It turns out that there is no current U.S. law requiring the labeling of foods which are derived from GMOs. This goes against current policy in many countries worldwide, including some countries of the European Union, Japan and New Zealand, which restrict or ban the production and sale of foods derived from GMOs (Examiner GMOs). If you, however, agree that genetically modified foods should be labeled, you are not alone. In fact, the state of Vermont has recently passed a law requiring all foods made from GMOs (VT Approves GMO Labeling). Three counties in California (Medocino, Trinity and Marin) have also successfully banned genetically modified crops. Other potential bans are in the works in several states, including Connecticut and Maine. However, many U.S. states and countries worldwide have embraced the use of GMOs products in foods.
Obviously there exists a controversy regarding the safety of foods derived from GMOs for human consumption. Since all the world’s countries have very smart people living there and working in government and the sciences, why is there such inconsistency in policy? It seems the differences in policy go beyond human intelligence and are based more upon human emotion than upon proven scientific facts. Some argue that GMOs could contain new toxins, have different nutrient content or lead to the development of new food allergies. Others express concern about the emergence of herbicide-resistant ‘super weeds’ and insecticide-resistant ‘super bugs’. These are noteworthy concerns, but so far, these fears have not been backed up by scientific study. Only time will tell. In the meantime, will you choose GMO-free foods?
Many of us probably know that eating a very-high-fat diet will not only make us gain weight, but it will also increase our risk of heart disease. But surprisingly, there are 2 disparate population groups that, notably, consume very high quantities of dietary fats, yet have a very low incidence of cardiovascular disease, polar bears and traditional Alaskan Eskimos. How is that possible? Does it have to do with the types of fats they eat, or to specific physiological adaptations? The answer is yes, to both of these questions.
A recent study published in the highly touted scientific journal Cell (Polar Bear Study), showed that polar bears and brown bears diverged in evolutionary history less than 500,000 years ago. This is a surprisingly short time, in evolutionary terms. During this time, polar bears moved north, subsisted on a blubber-rich diet of primarily marine mammals and fish, and became profoundly obese. Interestingly though, these bears do not develop fatty deposits in blood vessels (atherosclerotic plaques) or suffer from cardiovascular diseases (CVDs) that afflict most humans with diets rich in fat. How can that be? The answer to this seemingly paradoxical question was revealed by the gene studies in this publication, and was discussed recently in Science Daily (Researcher Interviews). The researchers found that polar bears had evolved several gene variants that helped them adapt to the high-fat diet. These variants were in genes which related to fatty acid metabolism and cardiovascular function. The researchers concluded that this study may provide insight into how to protect humans from the ill effects of consuming too much dietary fat.
The second group mentioned above, arctic Eskimos called the Intuits, also eat high-fat diets and have traditionally had very low incidence of CVD. This has been referred to as the ‘Intuit Paradox’ (Discover Magazine). The Intuits historically ate a high-fat diet consisting of seal and walrus meat and other blubbery marine mammals. Although we don’t know about specific gene variants in this population relating to heart disease, we do know that the composition of fat they consumed is very different from fat consumed today by most Americans. The Intuit diet was traditionally high in mono- and polyunsaturated fatty acids (and protective omega-3 fatty acids), and low in saturated and trans fats. This seems rather unexpected since most of us know that animal fats are high in saturated fat. It had to do with the source of the fats. It turns out the wild-animal fats are different (less saturated fat; higher in monounsaturated fats, like in olive oil) from farm-animal fats and processed fats (which also contain damaging trans fats). Moreover, cold water fishes and marine animal fats are particularly rich in polyunsaturated fats and omega-3 fatty acids.
So this then leaves us with 3 options if we choose to consume lots of dietary fats and still want to be healthy: 1) hope that we rapidly evolve like the polar bears; 2) consume more fat from wild-caught animals; or 3) focus on fats derived from plant foods like seeds, nuts and whole grains. What will your choice be?
You have probably heard that we all should eat more fish and seafood, right? What you probably haven’t heard as much about is how the source and the type of fish you eat can influence not only nutrient intake levels but also the levels of certain contaminants you consume. This is a particular concern as some fish contain antibiotics, pesticides, or other chemicals, including mercury, polychlorinated biphenyls (PCBs) and dioxins. For some individuals, for example pregnant women, this is an issue of real importance as these substances can cause harm to the developing fetus.
Despite these potential risks, it is generally accepted in the nutrition community that fish is a healthy dietary choice and regular consumption can have a positive impact on overall health. For example, the American Heart Association recommends eating fatty fish at least two times a week (AHA Omega-3 FAs), and diets such as the Mediterranean and DASH diet also promote fish consumption. Certain fish (e.g. salmon) contain high levels of omega-3 fatty acids which have anti-inflammatory properties, and may decrease risk of heart arrhythmias and blood clotting, and thus be protective against heart disease. Fish is also high in protein yet low in saturated fats.
This then leaves us in a quandary. How are we to eat more fish and other seafood, yet avoid exposing ourselves to dangerous environmental contaminants? The answer lies in the type of fish we consume, whether it was farm raised or caught in the wild and the frequency with which we consume the fish. Let’s look at species first. Contaminants are most likely to be present in older, larger predatory fish, such as shark, swordfish, king Mackerel and tilefish (Mayo Clinic Fish Info). The U.S. Food and Drug Administration (FDA) thus recommends that young children and pregnant and lactating women avoid eating these fish. It is also important to keep in mind, that not all fish and other seafood are high in omega-3 fatty acids. Some however, contain significant levels of omega-3 fatty acids and also have lower levels of environmental contaminants. These include salmon, canned light tuna, shrimp, pollock and catfish, which then are the best choice for consumers.
Two other issues to consider are the source of the fish and whether taking fish oil supplements is a good alternative. As you may or may not know, many fish such as tilapia are raised in “fish farms”. These aquaculture facilities raise large numbers of fish in relatively tight quarters. This leads to an increase in the risk for infection and other illnesses; antibiotics are thus routinely used in this setting. It is also important to consider whether the fish was imported into the U.S. from another country, as the inspection process may not be so robust. Moreover, there is some evidence that the nutrient content of wild caught fish is higher, but the price may also be higher. And lastly, there is emerging evidence in the nutritional sciences world that fish oil supplements do NOT provide the same health benefits that regular consumption of certain fish.
In summary, eating fish is good for us, but we have to be educated to realize the greatest health benefits. This general rationale also applies to many other aspects of healthy eating, such as choosing fruits and vegetables with the lowest levels of contaminating pesticides. So, learn, procure, cook and enjoy!
(written with the creative assistance of Avery Bramnik and Nicole Solomon, both University of Florida undergraduate students)