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Paleo Diet: Are the Cavemen our Healthiest Ancestors?

I first heard about the paleo diet as a junior in high school. A close friend was eating burgers without buns, and I inquired why. When she told me she was on the paleo diet, I was intrigued and immediately asked her to explain it. In simplest terms, the paleo diet is eating like a caveman. This means only eating foods you could hunt or gather (meat, fish, veggies, seeds, etc.) as opposed to processed foods (pasta, candy, cereal, etc.). To be honest, I was skeptical of this diet. For today’s post, let’s delve into the facts behind the paleo diet to find out how it affects your health!

In a 2009 study, nine healthy participants had their mineral levels examined as they switched diets. For the first three days of the study, participants ate as they normally would. The following three days consisted of meals with increased potassium and fiber levels. After that, the participants ate prepared meals designed by a nutrition software for the remainder of the study. Participants were not supposed to gain or lose weight so calorie intakes were adjusted if weights shifted. Participants were also instructed not to increase activity levels or take any medications. The results of the study reported multiple mineral concentration changes in urine excretion, the most notable being an increase in potassium and a decrease in sodium. A significant reduction in total cholesterol and lowered blood lipid levels were also a result of the paleo diet. The conclusions of this study included the previous results, along with the simple statement that the paleo diet does affect your health in a positive manner and it does so rapidly (Frassetto, Schloetter, Mietus-Synder, Morris, & Sebastian, 2009).

A more recent study focused on the blood lipid levels while on the paleo diet. Forty-four participants went on the paleo diet for 10 weeks, while also doing a CrossFit based circuit training program during the study. No specific amounts of food were recommended to the  participants as to mimic real eating patterns. The results of the study differed for those who already had optimal blood lipid values and those who had poor blood lipid values. While everyone lost weight with the combination of the diet and circuit training, the difference was in the post-study blood lipid levels. Those who had optimal levels were not able to maintain those levels, but those with poor levels were able to increase theirs. This lead to the conclusion that the paleo diet works better for those who are already unhealthy. This study also noted the limit of dairy, as it it contains necessary nutrients that are not easily replaced by non-dairy products (Pitt 2016).

Despite these two studies having valid results, Smith, Trexler, Sommer, Starkoff, and Devor state that the paleo diet is overhyped and under-researched. Many paleo diet claims are made by celebrities and not backed by science. While the paleo diet does have some health benefits, this article compared numerous studies and the results were not in total agreement. Thus, more research is needed on the paleo diet in order to confirm its benefits (2014).

In conclusion, the paleo diet has some benefits depending on your own personal health but needs further research in order to affirm the definite results of the diet.

Sources:

Frassetto, L. A., Schloetter, M., Mietus-Synder, M., Morris, R. C., & Sebastian, A. (2009). Metabolic and physiologic improvements from consuming a paleolithic, hunter-gatherer type diet. European journal of clinical nutrition, 63(8), 947-955

Pitt, C. E. (2016). Cutting through the Paleo hype: The evidence for the Palaeolithic diet. Australian family physician, 45(1), 35.

Smith, M. M., Trexler, E. T., Sommer, A. J., Starkoff, B. E., & Devor, S. T. (2014). Unrestricted Paleolithic Diet is Associated with Unfavorable Changes to Blood Lipids in Healthy Subjects. International Journal of Exercise Science, 7(2).

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Superfoods: Are They Saving Your Life?

Have you ever eaten a supposed superfood because of its moniker? Ordered an acai smoothie or a kale salad because these foods are apparently better than other fruits and vegetables? I know I have. However, never have I noticed a difference in my health from eating said foods. This leads me to my next question: are superfoods actually that super? Today’s post will delve into the nutritional value of superfoods and more!

While it has been shown that the use of the term positively impacted sales of the advertised superfoods, not many are sure of what a “superfood” actually entails. Let’s determine what a superfood is. This is definitely easier said than done, because superfoods don’t have a concrete definition. It used to describe “functional foods,” but it is now considered an umbrella term for foods with health-promoting benefits or disease-preventing properties beyond the usual. That broad definition is used in the general sense, however, in academia, superfood is used to describe energy dense foods (Lunn, 2006).

Dissecting the general description of a superfood, I wonder if the foods actually prevent diseases. Lunn (2006) states that there is no solid evidence that specific foods or their components have the ability to prevent certain diseases. With such a broad definition, one could argue that broccoli is a superfood due to its ability to induce anti-carcinogenic defense mechanisms.

A 2013 study looked at five exotic so-called superfoods (goji berries, pomegranates, chia seeds, acai berries, and mangosteen) and examined their nutritional content. Using scientific technology, the mineral content of multiple .25 mg or mL sized samples of each food were analyzed. Juices, capsules, and the actual food were used. Even though all of the foods tested on are nutrient dense and known to support the immune system, the researchers wanted to investigate how they contribute to our diets using Recommended Daily Allowance data.

The goji berries were found to be high in potassium and sodium (13-17 mg/g and 3.8-7.1 mg/g, respectively) and are considered a high contributor to diets. However, it should be kept in mind that the goji berry juice was less concentrated than the berries and capsules and thus should not be drank with the intent of fulfilling your necessary nutrients. This pattern of juices being less in mineral concentration is true for the other foods as well. Acai juice and mangosteen juice were examined, both having exceptionally low mineral contents and not contributing to daily diets. Pomegranates held a relatively high concentration of potassium compared to other elements in the fruit but did not compare to the concentrations found in the goji berries and chia seeds. The chia seeds were found to have large concentrations of calcium, potassium, magnesium, and phosphorus (all 3-11 mg/g), much higher than the other foods analyzed( (Llorent-Martínez, Fernández-de Córdova, Ortega-Barrales, & Ruiz-Medina, 2016).

Of the five examined, only two of the fruits appear to have relatively “super” concentrations of minerals. Does this mean we cannot trust the “superfood” label? Personally, I think that the term is used to market certain foods (that may or may not be exceptionally beneficial) to the public. While yes, some of the foods will have high concentrations of important minerals, the public should not take the superfood name at a surface level. Look into the nutritional value of the fruits and vegetables you’re eating! The superfood label may be lying to you.

Although evidence does not necessarily support superfoods, it does support what I call a superdiet. A superdiet being a balanced diet, not just focusing on superfoods. The label often implies that the superfoods should be included in your diet at the expense of non-superfoods. However, a range of fruits and vegetables is much healthier than fixating on only supposed superfoods (Rozin, 2005). Hopefully this makes you think twice when you see the newest list of superfoods come out!

Sources:

Llorent-Martínez, E. J., Fernández-de Córdova, M. L., Ortega-Barrales, P., & Ruiz-Medina, A. (2013). Characterization and comparison of the chemical composition of exotic superfoods. Microchemical Journal, 110, 444-451.

Lunn, K. (2006). Superfoods. Nutrition Bulletin, 31(3), 171-171.

Rozin, P. (2005). The meaning of food in our lives: a cross-cultural perspective on eating and well-being. Journal of nutrition education and behavior, 37, S107-S112.

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Fitbits: Are They Really Helping You Get Fit?

As a start to my blog, I thought I’d go with a topic that is almost universal to the public: Fitbits. Although I have never owned a Fitbit, I have owned an electronic step counter and my phone tracks my steps and distance. From my own observations, neither of these devices ever seemed completely accurate, especially from my phone. However, my close friends and family members own Fitbits and love its technology, along with the look. Are positive opinions enough to prove Fitbits worth the price? In today’s post, I’ll discuss the reliability and validity of the device, along with if they actually help you lose weight. 

A 2015 study found that the step counting technology of a Fitbit has no significant differences when compared to an observed counting. The researchers had participants use a treadmill at five different speeds while wearing a Fitbit One (a hip-based Fitbit). The step count and distance was recorded for each participant. Data came from the Fitbit One, observations (step counting), and the treadmill monitor (distance). While the step counts were found to be accurate, the distance measure was not reliable at any of the speeds (Takacs et al., 2015).

Another study confirmed these results with a similar procedure but with wrist-based Fitbits (on Amazon.com here) and hip-based Fitbits (on Amazon.com here).  It also compared the energy expenditure (calories burned) reported by the Fitbit and by gas exchange calorimetry. While the study did find that the step counting and calorie-burning counting was accurate, this is true more so in the hip-based Fitbit than the wrist-based Fitbit (Diaz et al., 2014). With these studies, we can ultimately conclude that while the step counting feature is valid in both wrist- and hip-based devices, the other features are much more accurate in the hip-based Fitbit.  Keep this in mind when looking for a new health device!

Now that we’ve discussed the reliability of the data reported by the Fitbit, let’s talk about if using a Fitbit actually helps you achieve your weight goal or be healthier. When looking at behavioral strategies used in evidence-based weight loss interventions, the Fitbit iPhone app only used 15% of the 20 strategies, leaving out features that track eating patterns, negative thinking, and relapse prevention, among others. The app does include a calorie counter, dietary goal-maker, and weight-loss goal-maker. While making goals is essential in weight-loss, the missing factors are essential to staying on track with those goals (Pagoto, Schneider, Jojic, DeBiasse, & Mann, 2013).

While the Fitbit does contain a majority of the behavioral strategies found necessary to lose weight, there is a still a slight psychological persuasion. Based on thirty interviews with those who use Fitbits or similar devices, an immediate increase in activity levels occurs when using the device. Seeing the step count on the device change in real-time acts as an extra motivation for device owners to reach and surpass their step-count goals, but not necessarily their weight-loss goals. Getting credit for their actions and  in-app achievement badges (i.e., “lifetime distance of 500 miles”) also act as a motivations. Interviewees reported taking the stairs more and standing while working (rather than sitting) as an effect of wearing a Fitbit or similar device. Over elongated use, it was found that even though people stopped paying attention to the physical device, they continued to mentally count steps, having calculated how long the walk to work or the walk to the train station is over time (Fritz, Hunag, Murphy, & Zimmerman, 2014). Although a direct connection between wearing a Fitbit and weight loss was not found, there is a relationship between wearing a Fitbit and increased activity levels.

To conclude, I’ll recap what was discussed in today’s post. Hip-based Fitbits are more accurate than wrist-based Fitbits in step counting and calories-burned counting. With regards to distance, the reported number from the Fitbit was not found to be reliable. A concrete relationship was not found between weight loss and wearing a Fitbit, but wearing a Fitbit does increase activity levels, which helps in achieving a weight-loss goal. Personally, I recommend getting a hip-based Fitbit (such as this) to get the most accurate results. As far as motivation goes, the type of Fitbit does not appear to matter. According to the studies presented here, the Fitbit appears to be worth the price but not purely as a device to help you lose weight.

Sources:

Diaz, K. M., Krupka, D. J., Chang, M. J., Peacock, J., Ma, Y., Goldsmith, J., ... & Davidson, K. W. (2015). Fitbit®: An accurate and reliable device for wireless physical activity tracking. International journal of cardiology, 185, 138.

Fritz, T., Huang, E. M., Murphy, G. C., & Zimmermann, T. (2014, April). Persuasive technology in the real world: a study of long-term use of activity sensing devices for fitness. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems(pp. 487-496). ACM.

Pagoto, S., Schneider, K., Jojic, M., DeBiasse, M., & Mann, D. (2013). Evidence-based strategies in weight-loss mobile apps. American journal of preventive medicine, 45(5), 576-582.

Takacs, J., Pollock, C. L., Guenther, J. R., Bahar, M., Napier, C., & Hunt, M. A. (2014). Validation of the Fitbit One activity monitor device during treadmill walking. Journal of Science and Medicine in Sport, 17(5), 496-500.

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Welcome!

Welcome to my blog, Science&&Life! Stay tuned for the first post...