The gut microbiota is the diverse community of microorganisms that reside within the gastrointestinal tract. The importance of the composition (what types of microorganisms), function (what they are doing), and the metabolites (what are they producing) has been highlighted in health and disease. In the case of chronic kidney disease (CKD), it is of great interest as the gut microbiota has been linked to the disease itself and the progression of kidney dysfunction.

The gut microbiota in chronic kidney disease

In CKD there are changes at the level of composition and function (e.g., enzymatic capacity) and metabolites produced by gut microbes. These changes have been assessed by examining mostly stool samples through experimental models (e.g., mouse or rat models of kidney disease by removing a large portion of the kidneys (5/6th) or by providing a toxic agent in the diet (i.e., adenine)) or in individuals with CKD not yet on dialysis and those undergoing dialysis treatment.

The changes in composition of the gut microbiota include having less bacterial species richness (amount of diversity within a sample) and an increased abundance of bacteria that are considered pathogenic or “bad”, while there is a reduction in the abundance of bacteria that are traditionally considered symbiotic or “good”. With these changes, the gut microbiota of CKD patients is considered dysbiotic or out of balance.

At the functional level, it has been reported that the fecal samples from individuals undergoing dialysis have an increased amount of enzymes that produce toxins that are increased as kidney function declines, mostly those that produce protein degradation metabolites (i.e., urea, uric acid, tyrosine, and tryptophan). Also, there is a decrease in the enzymes needed for the production of short-chain fatty acids, which are mostly produced from the fermentation of dietary fiber and thus are traditionally considered “good”.

At the metabolite level, mirroring the effect on the enzymes needed for the production of toxins derived from amino acid and protein degradation, metabolites such as indoles and phenols derived exclusively from the gut microbes are increased in the plasma of CKD patients.

Therapies that target the composition, function, and metabolites produced are of great interest in the CKD community

Due to the changes mentioned above, therapies that target the composition of the gut microbiota, the function of the gut microbiota, and what the gut microbes are producing are of great interest to try to reduce the burden of CKD. These therapies may include the use of pro-, pre-, and synbiotics.

The use of probiotics in CKD is not supported by the current evidence

Probiotics are live microorganisms that when consumed in specific amounts may give the individual a benefit. There are several probiotic bacteria, including species and strains within the Bifidobacterium and Lactobacillus families. Probiotic bacteria have been studied extensively in healthy individuals and those with several diseases. Some of the benefits in patients with CKD may include binding to pathogenic bacteria, decreased levels of inflammation, reduction of toxins produced by the microbes, and improvement of the health of the gastrointestinal tract.

Although the possible beneficial effects of supplementation with probiotics sounds promising, the current evidence does not support their use. In a recent meta-analysis by McFarlane and collaborators, they found no benefit of the use of probiotics on the levels of serum urea, indoles, and phenols. In fact, when you go to the individual studies, some of them found increases in these toxins and markers of inflammation, while they report no changes in the composition of the gut microbiota.

The use of prebiotics may have a beneficial effect in CKD

Prebiotics are substrates (including dietary fibers that are fermented by the microbes) that are used by the gut microbes producing short-chain fatty acids to provide a benefit to the host. While probiotics have not been associated with beneficial effects, the use of prebiotics may provide a better solution in patients with CKD.

The use of prebiotic substances in CKD has been limited to the use of prebiotic fibers, such as resistant starch, oligofructose-enriched inulin, and arabinoxylans, among others. In the meta-analysis by McFarlane and collaborators, they found that the use of prebiotics reduced levels of serum urea. However, there was no effect on other metabolites produced by gut microbes or the composition of the gut microbiota.

Not pro- or prebiotics, but what about synbiotics?

Synbiotics are the combination of pro- and prebiotics. While the use of pro- or prebiotics on their own have not yielded the expected results, the use of synbiotics seems promising.

Rossi and collaborators examined the effect of a synbiotic in patients with CKD not yet on dialysis. The synbiotic contained 15g of a combination of prebiotic fibers and a probiotic with nine strains from the Lactobacillus, Bifidobacteria, and Streptococcus genera. They found decreases in serum indoxyl sulfate (derived from the fermentation of the amino acid tryptophan) and changes in the composition of the gut microbiota.

Viramontes-Hörner and collaborators found that the use of a probiotic gel with 2.3g of prebiotic fiber, a probiotic with Lactobacillus and Bifidobacterium, omega-3 fatty acids and vitamins decreased the severity of gastrointestinal symptoms, a highly prevalent problem in patients with CKD.

So, should we recommend the use of pro-, pre-, and synbiotics in patients with CKD?

Although the fundamental idea makes sense, the use of these interventions targeting the gut microbiota has not produced the expected results. However, CKD is a complex disease and individuals with reduced kidney function are often recommended a restrictive diet low in dietary fiber and a variety of medications with unknown effects on the gut microbiome. This may be the reason why some of these interventions may not be enough to cause a change in the gut microbiome. Hopefully, future interventions will apply a more holistic approach to assess and target the gut microbiome in patients with CKD.

According to the United Nations the aging population is growing and by 2050 the number of people aged 60 years old will reach 2 billion worldwide. With the aging population the prevalence of age-related disease is predicted to increase. An example of an age-related disease is neurodegeneration.  Dementia can be a result of several pathologies including increased levels of Lewy bodies (abnormal aggregates of protein in nerve cells), as seen in Parkinson’s disease.

Cerebrovascular disease is the second most common cause of dementia and is a result of  changes in blood flow to or within the brain. Blood flow in the brain can change because of hypertension, diabetes, smoking, and hypercholesterolemia. Patients with cerebrovascular disease experience cognitive impairment, specifically when trying to remember things or plan events/trips. It is important to note that symptoms can vary from patient to patient. A type of cerebrovascular disease is vascular cognitive impairment (VCI).

Nutrition is a modifiable risk factor for diseases of aging. As people age their ability to absorb nutrients from their diet decreases.  Several studies have reported that changes in B-vitamin absorption may play a role in the onset and progression of dementia. Additionally, a study by researchers in the United Kingdom shows that B-vitamin supplementation reduced brain volume loss in areas associated with cognitive decline. A recent international consensus statement from leaders in the field suggests that deficiencies in B-vitamin metabolism should be considered when screening dementia patients. My research using model organisms has tried to understand the disease processes associated with dementia.

Using a mouse model of VCI we have reported that deficiencies in folic acid, either dietary or genetic affect the onset and progression of VCI. Using the Morris water maze task we report that mice with VCI and folate deficiency performed significantly worse compared to controls. We assessed changes in the brain using MRI and interestingly found that folate deficiency changed the vasculature in the brains of mice with VCI. Because of either a genetic or dietary folate deficiency all the mice had increased levels of homocysteine.

Our results suggest that it is not elevated levels of homocysteine making the brain more vulnerable to damage, but the deficiency in folic acid, either dietary or genetic, that changes the brain. In the cell folic acid is involved in DNA synthesis and repair as well as methylation. These are vital functions for normal cell function. Therefore, reduced levels of folate may be changing the cells in the brain and making them more vulnerable to certain types of damage. We think that high levels of homocysteine may just be an indication of some deficiency (e.g. reduced dietary intake of folic acid). Maintaining normal levels of homocysteine are needed, since studies in humans have shown that elevated levels of homocysteine are a risk factor for neurodegenerative diseases and that reducing them is beneficial.

 

Sweeteners_Sanae Ferreira

Sweeteners_Sanae Ferreira

In the case of Shakespeare, a rose is a rose is a rose – all smell sweet. But, in the case of sweeteners, the story is not quite so simple.

 

Here are a couple of scenarios that may look familiar to you:

 

– You’ve sat down at your favorite breakfast place, and your server has asked if you would like some coffee or tea while you consider the menu. A carafe appears, your cup is full, and you instinctively reach for the narrow box containing a rainbow of packets. You reach for one, but are curious about the rest – what are they really?

– You’re at the store, trying to buy something to drink, and there are words you don’t recognize on the label next to “sugar-free.”

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Choose your own adventure: Which scenario do you identify with?

  1. You wake up crabby and groggy each morning, reluctantly rolling out of bed after hitting ‘snooze’ three times at a minimum. You curse the morning as you shock your system with a splash of cold water- a cruel, yet necessary ritual. You grab strong coffee and a slightly stale bear claw pastry as an afterthought on the way out the door. This caffeine/sugar combination gives you life for a few hours until you succumb to intense hunger pangs at 11:30am. Take-out lunch quenches the stomach rumbling and dulls your throbbing temples, and you turbulently sail until the 3 o’clock hour, after which point productivity squeals to a halt. More coffee, a fistful of candy from the office jar (and some nuts and carrots in a half-hearted attempt to be healthy) offer a temporary solution. 5pm rolls around, and you leave work in a ravenous, foggy state of mind. You planned to hit the gym, but a date with microwave dinner and Vino are the way to your heart tonight. Once home, you sigh a great, empty sigh as you kick your gym bag to the corner of your room and fall face-first on the couch in one fell swoop.
  2. You wake up as early morning light streams through the cracks in your blinds, pleasantly surprised your alarm clock is set to ring in two minutes. You lie still for a moment, calmly preparing for the day ahead. You move through your morning routine that leaves ample time for breakfast, coffee, and reading the paper. Your philosophy hasn’t failed you yet: ‘Make it fast, eat it slow’: Today’s breakfast is a chopped apple, Greek yogurt, cinnamon, and steel-cut oatmeal topped with honey and slivered almonds. You grab your lunch from the fridge (a colorful salmon, farro, roasted veggie and garbanzo bean salad prepped the night before) on the way out the door. Around 11:30am, you hear a chorus of yawns around your open-layout office; Although wide awake, your stomach gently requests more fuel. Lunch powers you through a productive afternoon with a walking meeting (your preference) and impressive brainstorm session for an exciting new research study that integrates Nutrition, Psychology, and Neuroscience. At 4pm, you re-fuel body and mind with walnuts and blueberries for your planned strength training workout. Energized once more, you grab dinner out with friends- your favorite way to socialize! Roasted herb chicken, bread with olive oil, kalamata olives, and caramelized seasonal vegetables are the way to your heart tonight. Although it’s been a full day, you feel mentally and physically strong.

 

The above scenarios differ like night and day; Although each is dramatized for effect, be honest- most of us can identify with one situation more strongly than the other. Go ahead and select the category that resonates most with you, and let’s dive deeper with a brief brainstorm. What factors make the above scenarios glaringly different?

  1. Person A failed to plan, and Person B practically has a degree in Life-Skills 101
  2. Person A’s job is a drain, while Person B is energized by his/her work
  3. Person A might suffer from depression, while Person B likely does not

So far, so good: Each observation is a deeper reflection of the individuals’ moods. Person A is lethargic, fatigued, unmotivated, and ‘empty,’ while Person B is energized, mentally sharp, mindfully present, and fulfilled.

Excellent, let’s pursue this lead! Consider this: What deeper, underlying factor might account for these distinct moods? Consider one more glaring difference between scenario A and B, this time considering trends in the foods consumed:

  1. Simple carbohydrates, high sodium, and high saturated fat, with a modest sprinkling of vitamins, minerals, and fiber from primarily packaged-foods
  2. Whole grains, lean protein, ample produce, monounsaturated and polyunsaturated fats, lots of fiber, probiotics, vitamins and minerals, and all primarily from whole-food sources

Credit: Easy Recipe Depot

Person A and B both know that their food choices influence their outward appearances- after all, you are what you eat! Digging deeper, however, we see that Person B still has an advantage: This person also understands that one’s food choices influence mental state and behavior! Whether intuitively or intentionally, this person knows a thing or two about an emerging research area called ‘Nutritional Psychiatry.’

Credit: Mind Brighton & Hove

Let’s briefly turn to the research to get the low-down on Nutritional Psychiatry:

If you begin your knowledge quest with a Google search of the term, you’ll find a variety of media reports and research foundations devoted to the topic. Case in point:

The Harvard Health blog published an article called “Food and Mood-Is there a connection?” This article articulates how certain dietary patterns may protect mental health. More specifically, a Mediterranean diet pattern rich in fruits, vegetables, olive oil, whole grains, and lean protein such as chicken and fish, and low in red meat and unhealthy fats may provide promising benefits. Important to note, however, is that one single dietary factor or lifestyle factor is unlikely to affect mental health independently.

The Conversation explains that although research is in early stages, “it is now known that many mental health conditions are caused by inflammation in the brain. This inflammatory response [may be] associated with a lack of nutrients…Recent research has shown that food supplements such as zinc, magnesium, omega 3, and vitamins B and D3 can help improve people’s mood, relieve anxiety and depression and improve the mental capacity of people with Alzheimer’s.

(Psst…see that hyperlink on ‘recent research?’ That’s a link to an original study! Click it, friends!)

-A research foundation called the International Society of Nutritional Psychiatry Research will direct you towards “high quality evidence for nutritional approaches to the prevention and treatment of mental disorders.”

Both sources are good places to start, but our search has just begun! You can either scour each article for links to official research studies written by the research teams themselves, and read such study (Rule of thumb: Media reports are for entertainment first, and comprehensive education second or third or fourth). Alternatively, you may turn to Pubmed and pull up a review article on ‘Nutritional Psychiatry.’ (What’s a review article? Aside from being my preferred, reader-friendly way to learn about science, here’s a description)

The fourth result in our original Google search is conveniently a link to a 2017 review paper called “Nutritional Psychiatry-Where to Next?” This article explains that “A consistent evidence base from the observational literature confirms that the quality of individuals’ diets is related to their risk for common mental disorders, such as depression.”

While promising so far, comprehensive research is still needed in this area, as articulately stated by the same authors: “Key challenges for the field are to…replicate, refine and scale up promising clinical and population level dietary strategies; identify a clear set of biological pathways and targets that mediate the identified associations; conduct scientifically rigorous nutraceutical and ‘psychobiotic’ interventions that also examine predictors of treatment response; conduct observational and experimental studies in psychosis focused on dietary and related risk factors and treatments; and continue to advocate for policy change to improve the food environment at the population level.”

Breastfeeding as an issue of significance in the world of public health and nutrition has gained considerable traction in recent months. With globally publicized opposition by the US to the World Health Assembly Resolution on Infant and Young Child Feeding (triggered by severe restrictions on milk products for older infants and young children) and reports of coercion to further corporate interests, the issue is of great pertinence in today’s times. It being World Breastfeeding Week, this blog will delve into the science of breastfeeding, a nutrition-focused behavior that has amassed a tremendous body of evidence in its favor when concerning infant and young child health [1].

The Lancet series published in 2016 describes both the micro and macro level benefits of breastfeeding for infants in countries of all economic strata. One paper [2] from the series estimates that approximately 823,000 annual deaths among children <5 years of age and 20,000 annual deaths of women from breast cancer can be avoided through the promotion of improved breastfeeding practices. Additionally, breastfeeding has long lasting impacts on morbidity and improves the cognitive capacity and educational potential of children, with economic benefits including higher wages in adulthood [2]. Greater benefits are achieved with longer durations of breastfeeding, and this behavior has impact on morbidity with evidence showing protective benefits against diarrhea, respiratory infections, and asthma [3].

Additionally, a growing body of evidence shows overwhelming support for breastfeeding as protective behavior against long-term health outcomes related to non-communicable diseases including obesity [3]. An analysis of 113 studies shows that longer durations of breastfeeding are associated with a 26% reduction (95% CI: 22-30) in the odds of obesity across income groups. Another pooled analysis of 11 studies showed a 35% reduction (95% CI: 14-51) in the incidence of type 2 diabetes [3]. Prior work has shown that breastfeeding confers protection against obesity later in life, with lower prevalence rates after adjusting for confounders such as socioeconomic status, birthweight and sex [4].

Recent papers published in the American Journal of Clinical Nutrition highlight the nuanced impact of breastfeeding on child growth trajectories. A study by Kramer et al. (2018) showed, using various different statistical analyses, a causal effect of randomization to a breastfeeding promotion intervention on growth during the first 2-3 months of life [5]. Additionally, these authors noted that children in a breastfeeding intervention group and those who were breastfed for ≥12 months experienced faster growth when compared to those in the control group or those breastfed for <12 months, particularly during the first 2-3 months. The differences in growth velocity between groups was lower in subsequent months and almost equalized by 12 months of age.

A study by Eny et al. conducted in Canada found that maternal BMI was positively correlated to infant BMI [6]. These authors note that maternal BMI has been shown to modify BMI growth rates among children beginning at birth up to 12 years of age [7]. These authors note that the trajectories for growth differed by breastfeeding duration, maternal BMI and birth weight from 1-3 months of age.

Results from these studies and others highlight the need for more prospective research to assess how, when and whether breastfeeding practices influence infant weight gain, and what factors within breastmilk impact lean and fat mass growth [8]. Overall, the case for early initiation, exclusivity of breastfeeding for the first 6 months and continued breastfeeding up to 2 years remain strong and programs, policies and incentives to encourage and promote adequate breastfeeding behaviors remain the need of the hour. So this World Breastfeeding Week, may mothers’ across the world be motivated, encouraged and supported to continue gifting their young one of the most valuable gifts nature has accorded us!

References:
[1] Jacobs, A. (2018). Opposition to breast-feeding resolution by the US stuns world health officials. Retrieved from: https://www.nytimes.com/2018/07/08/health/world-health-breastfeeding-ecuador-trump.html
[2] Rollins, N.C., Bhandari, N., Hajeebhoy, N., Horton, S., Lutter, C.K., Martines, J.C., Piwoz, E.G., Richter, L.M., Victora, C.G. (2016). Why invest, and what it will take to improve breastfeeding practices? Lancet, 387, 491-504.
[3] Victora, C.G., Bahl, R., Barros, A.J., Franca, G.V.A., Horton, S., Krasevec, J., Murch, S., Sankar, M.J., Walker, N., Rollins, N.C. (2016). Breastfeeding in the 21st century: epidemiology, mechanisms, and lifelong effect. Lancet, 287, 475-490.
[4] Armstrong, J., Reilly, J.J., & Child Health Information Team. (2002). Breastfeeding and lowering the risk of childhood obesity. Lancet, 359 (9322), 2003-2004.
[5] Kramer, M.S., Davies, N., Oken, E., Martin, R.M., Dahhou, M., Zhang, X., & Yang, S. (2018). Infant feeding and growth: putting the horse before the cart. American Journal of Clinical Nutrition, 107, 635-639.
[6] Eny, K.M., Anderson, L.N., Chen, Y., Lebovic, G., Pullenayegum, E., Parkin, P.C., Maguire, J.L., Birken, C.S. (2018). Breastfeeding duration, maternal body mass index, and birth weight are associated with differences in body mass index growth trajectories in early childhood. American Journal of Clinical Nutrition, 107, 584-592.
[7] Bornhorst, C., Siani, A., Russo, P., Kourides, Y., Sion, I., Molnar, D., Moreno, L.A., Rodrigues, G., Ben-Shlomo, Y., Howe, L., et al. (2016). Early life factors and inter-country heterogeneity in BMI growth trajectories of European children: the IDEFICS study. PLoS One, 2016:11:e0149268.
[8] Hay, W.W. Jr. (2018). Breastfeeding newborns and infants: some new food for thought about an old practice. American Journal of Clinical Nutrition, 107, 499-500.

Breastfeeding: Foundation of Life

World Breastfeeding Week is celebrated every year from August 1 – 7 across the globe to encourage breastfeeding and promote healthy practices from the earliest stages of life. This campaign is led by the World Alliance for Breastfeeding Action (WABA), a global network of organizations and individuals who work to promote and support breastfeeding practices worldwide. The 2018 slogan is “Breastfeeding: Foundation for Life”.

“In a world filled with inequality, crises and poverty, breastfeeding is the foundation of lifelong good health for babies and mothers.”

Latest Research on Breastfeeding

ASN’s four nutrition science journals often publish new research on breastfeeding, and there were many sessions on the topic at ASN’s annual meeting, Nutrition 2018. ASN also ensures the representation and support of breastfeeding research within our membership and scientific programs through a dedicated research interest section, Maternal, Perinatal, and Pediatric Nutrition. Members who belong to this group focus on the biology of nutrition as it impacts human development, and the role of nutrition on both short-and long-term outcomes in the mother, fetus, infant, and child.

New Research on Breastfeeding from American Journal of Clinical Nutrition

Breastfeeding newborns and infants: some new food for thought about an old practice

“Feeding newborns and infants is hardly a new topic, but these 2 articles provide some important new food for thought, and hopefully might stimulate appetite for studying how breastfeeding and human milk confer unique advantages on infant growth and development, as well as prevention of later life diseases such as obesity, which are programmed early in life.”

Breastfeeding duration, maternal body mass index, and birth weight are associated with differences in body mass index growth trajectories in early childhood

Infant feeding and growth: putting the horse before the cart

Current Knowledge on Micronutrients in Human Milk: Adequacy, Analysis, and Need for Research

This free supplement was published with the May 2018 issue of Advances in Nutrition. Articles included are:

Introduction to Current Knowledge on Micronutrients in Human Milk: Adequacy, Analysis, and Need for Research

Overview of Nutrients in Human Milk

Limitations of the Evidence Base Used to Set Recommended Nutrient Intakes for Infants and Lactating Women

Micronutrients in Human Milk: Analytical Methods

Retinol-to-Fat Ratio and Retinol Concentration in Human Milk Show Similar Time Trends and Associations with Maternal Factors at the Population Level: A Systematic Review and Meta-Analysis

Iodine in Human Milk: A Systematic Review

Vitamin B-12 in Human Milk: A Systematic Review

Breastfeeding and the Microbiome

ASN Fellow Dr. David Heber recently published a video Microbiome #3: Getting it Started. This is what he says:

“The Microbiome is established in the gut during breast feeding. While some bacteria enter the body during delivery and from the mother’s skin, the majority are formed from a special group of complex carbohydrates called Human Milk Oligosaccharides (HMO’s). There are about 150 HMO’s and they feed a single bacterial species called Bacteroides Infantilis which has a series of pumps on its surface bringing these sugars called oligosaccharides inside the cell to be digested. This bacteria is called an “inside” eater and does not share the HMO’s with other bacteria so it becomes the dominant bacteria in the gut Microbiome setting up the baby’s immune system. The breast milk has protein, fat, and lactose (the same sugar in cow’s milk) but is unique in having the 150 HMO’s. This is another reason why it is so important for women to breast feed their babies. Breastfeeding also removes 500 Calories per day from the Mom’s body helping with reducing pregnancy weight gain. During breast feeding women need to get extra protein, Calcium, vitamin D and B vitamins to replace what is being put out in breast milk!!”

Video shared with Dr. David Heber’s permission.

Calcium is traditionally considered the bone-health nutrient. This is because 99% of calcium is contained within the bone, in which calcium creates a mineral complex with phosphate (hydroxyapatite), giving bone its characteristic strength and function. However, besides forming part of bone, calcium is also involved in other functions, such as muscle function, nerve transmission, intracellular signaling, and others.

Bone is a very dynamic organ in which the rate of formation and resorption (or destruction) is different throughout the lifespan. During childhood and adolescence, the rate of formation is higher than the rate of resorption, leading to maximum bone gain. In older adults these rates are switched, causing loss of bone. This bone loss may lead to osteopenia, osteoporosis, and an increased risk of bone fractures.

Is an increased intake of calcium associated with reduced risk of fractures?

As a way to prevent bone loss and fractures in middle-aged and older adults, there is usually a push from public health initiatives and healthcare professionals to increase the intake of calcium. However, an increased intake of calcium (dietary + supplements) may not necessarily lead to fewer fractures. Two of the most recent systematic reviews and meta-analyses showed that increasing dietary calcium and the supplementation of calcium (and vitamin D) did not reduce the risk of fractures. However, this remains controversial as a previous meta-analysis showed that the supplementation of calcium and vitamin D was associated with a 15% risk reduction in middle-aged and older adults (community-dwelling and institutionalized).

 The use of calcium supplements may lead to a higher risk of cardiovascular disease

The hypothesis is that an increased intake of calcium may lead to a positive calcium balance (intake lower than output in urine + feces), in the absence of increased bone formation. This positive calcium balance may lead to the calcification of tissues other than the bone, such as the vasculature, increasing the risk of cardiovascular disease. However, this association remains controversial. A sub-analysis of the Multi‐Ethnic Study of Atherosclerosis (MESA), showed that those that had higher dietary calcium intake (without supplements) had a lower risk of coronary artery calcification, while those that were taking supplements had a higher risk. However, the National Osteoporosis Foundation and the American Society for Preventive Cardiology suggested that calcium intake (diet + supplements) that does not exceed the tolerable upper level of intake of 2000 to 2500mg/d is not associated with cardiovascular outcomes, and should be considered safe.

Special caution of high intake of calcium in subjects with reduced kidney function

A high intake of calcium, particularly those that use calcium supplements, may represent a problem for those with reduced kidney function, as they may not be able to excrete the extra calcium. In a study by Hill and collaborators, a calcium intake of 2500mg (1000 mg through diet + 1500mg from calcium carbonate), compared with a dietary calcium intake of 1000mg, led to 500mg of calcium retention in patients with reduced kidney function. Similarly, Spiegel and collaborators compared a diet with 800mg vs. 2000mg of calcium in subjects with normal and reduced kidney function. In those on the 2000mg calcium diet, there was a positive calcium balance, which was more marked in those with reduced kidney function. With these results, a calcium intake higher than 800-1000mg (diet + supplements) should be avoided in those patients with a reduced kidney function to prevent calcifications of tissues other than the bone.

Should health care professionals recommend a high intake of calcium?

The current evidence, in middle-aged and older adults, does not seem to support high calcium intakes (above the tolerable upper level) for the prevention of fractures. Additionally, high calcium intakes achieved with the use of supplements may be associated with increased risk of cardiovascular disease. However, the use of supplements may be useful for patients that have low calcium intake. Finally, special attention should be taken in patients with reduced kidney function, as a high intake (diet + supplements) may lead to an increased risk of cardiovascular disease.

 

What do I eat? That is a question most people ask themselves at least once a day. Imagine getting a prescription from your physician and vetted by a nutritionist to cook certain foods at home. The prescription is tailored to your personal needs, and your care team has received training as health coaches to help you successfully implement this new plan. This is culinary medicine.

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Which consumer are you?

The astute academic or health professional: You have a degree (one or more) in nutrition, you have PubMed bookmarked on your internet browser, and you spend your days dispelling nutrition myths and/or researching the next nutrition breakthrough.

The health foodie. You scour wholesome recipes online, you already know the nutrition trends for 2019, you make detailed grocery lists like it’s your job, you’re a #mealprepsunday veteran, and always know where to find the best deals for natural/organic/raw/fresh eats.

The bachelor/broke student: Is it cheap? Edible? Delicious? Easy to prepare? If yes, it goes in the cart.

The athlete with phenomenal sport skills, and (developing) culinary know-how: You know that the foods you eat influence your athletic performance. You are game for eating better, under one condition: you need quick/easy foods that pack a nutritional punch.

The busy parent: There are lunches to make, picky eaters to feed, and you can’t remember the last time you enjoyed a calm, healthy mealtime at home. Grocery shopping is typically a stressful battle between your healthy intentions, and the little ones’ demands for sugary cereals and flashy marketing.

Photo Credit: Lifehacker

Whether you identify with one or multiple distinct categories listed here, each one is unified by a few common underlying themes:

We all eat.

We crave amazing flavors.

There are never enough hours in the day.

We really do have good intentions; We want to eat well.

Assuming we don’t grow/hunt/gather our own food, we cross paths with one another for a common purpose: Food Shopping! On that note, we’ve been exposed to the same rules of thumb for healthy grocery shopping:

-Shop the perimeter!

-Steer clear of the middle aisles!

The way I see it, there are two types of people in this world: Those who love the center aisles (but could use a little strategy for picking the best options), and those who openly shun those aisles (but are secretly curious to explore the forbidden foods within).

As a health professional, it’s my duty to pass along this tried-and-true advice. But as a real-life RD on a budget, I hear you: Those middle aisles are mighty tempting, so what’s a guy/girl to do?

Take a deep breath, direct that grocery cart towards those center aisles, keep your eye on the prize and walk with intention because you have a fool-proof plan. Healthy shoppers, unite! Today, you’ll conquer those middle aisles like the savvy consumer you are.

Photo Credit: The Sports Nutrition Coach

Your strategy: Divide and conquer by food group like so:

Whole grains, legumes, and pseudograins: Instant oatmeal, frozen brown rice or quinoa (that’s a pseudograin), ready-to-serve plain cooked rice, Grape Nuts (for impressive iron and fiber content), popcorn, Vaccuum packed pre-cooked lentils (that’s a legume), whole grain bread (can you find bread with 0-1g sugar per serving? Can you find fiber above 2g per serving?)

Fruits and vegetables: Frozen is your friend! These items are picked at peak ripeness and flash-frozen immediately afterwards. Canned items are fine as well (in light syrup or water). Can you get all colors of the rainbow?

Protein: Canned beans, canned tuna, canned chicken, canned salmon, frozen chicken strips (no breading), hummus

Dairy: single serve plain Greek yogurt (Ok, you’ll find this in the perishables, but this is too versatile not to include), string cheese

Fats: Olives, frozen Cool Whip, prepared guacamole

Snacks: Dark chocolate (Pro-tip: Pick one with single-digit grams sugar per serving), nuts (try pistachios, almonds, or walnuts), dried fruit, jerky, whole grain chips, hummus

Drinks: Chocolate milk

Spreads/flavorings: Sriracha, olive oil, balsamic vinegar, mustard, pesto

Photo credit: Smile Sandwich

 Once you return home from this über successful grocery trip, you’ll want to assemble some stellar meals using your new bounty. Try this one-day sample plan:

Breakfast: Yogurt cup topped with frozen fruit, Grape Nuts, nut butter (purchase single serve packets in a pinch!) Feeling extra hungry? Prepare a side of instant oatmeal

Lunch: Tuna sandwich (canned tuna mixed w/ mustard, Ezekiel bread). Side of green salad (found in deli section)

Snack: Handful of nuts, handful chips, and hummus

Post Workout: Classic PB&J, or chocolate milk

Dinner: Defrost that frozen rice, quinoa, or lentils, frozen veggies of choice, top w/ beans (and/or thawed ready-to-eat chicken), salsa, pre-made guacamole, and Sriracha

Dessert: 2-3 squares of dark chocolate, alongside frozen blueberries w/ a dollop of cream

Not everyone has a nutrition coach by their side, but you, ASN reader, have an edge. Use this guide to confidently navigate the previously forbidden center aisles. Print it, internalize it, share it. No nonsense, no gimmicks. Blasphemy? Hardly. Creative and backed in science? Absolutely.

The popularity of the essential polyunsaturated omega-3 fatty acids (O3FA) is on the rise. In 2017, O3FA achieved a spot on the top 20 foods and ingredients list that Americans are adding to their diets (The Hartman Group). In addition, the global fish oil market is expected to reach a whopping 4.08 billion dollars in the next four years!  The proposed health benefits are likely the driving force behind the increasing demand.

Despite their booming popularity, a large percentage of adults are not meeting the O3FA recommended intake. There are three primary O3FAs with distinct characteristics: alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Although commonly grouped under the umbrella term O3FAs, are all O3FAs created equal?

Unique Characteristics of O3FAs

Omega-3 fatty acids cannot be sufficiently produced in the body earning them the title of “essential fatty acids.” The plant-derived omega-3, ALA, is the parent precursor to EPA and DHA. Unfortunately, the conversion rate in our bodies is very low.  It is important to realize that in the process of metabolizing ALA to EPA and DHA, a series of anti-inflammatory markers are produced (leukotrienes, prostaglandins and thromboxane). As these anti-inflammatory metabolites are beneficial, direct EPA and DHA consumption is needed to meet bodily requirements.

Independent and Complementary Health Benefits

The majority of current research focuses on the health benefits of marine fatty acids.  DHA and EPA consumption portray an array of shared and complementary benefits related to the treatment of cardiovascular disease, depression diabetes, sleep disorders and more. DHA is more significantly associated with decreases in resting heart rate, blood pressure and with improvements in cellular membrane health due to its additional double bond and longer carbon chain. Increased cellular levels of EPA have been shown to benefit coronary heart disease, hypertension and to decrease inflammation. EPA and DHA are both associated with reduced gene expression related to fatty acid metabolism, reduced inflammation and oxidative stress.

Specific supplementation of ALA is not consistently associated with cardiovascular health. Although plant-derived ALA can be easily substituted in for excess omega-6 fatty acids (O6FAs). Research has shown that by reducing the O3FA:O6FA ratio, you can decrease bodily inflammation, increase anti-inflammatory markers and more efficiently utilize EPA and DHA.

An ALA, EPA and DHA-Rich Diet

The 2015-2020 Dietary Guidelines for Americans recommends that healthy adults consume at least 8 ounces of a variety of non-fried fatty seafood per week. For EPA and DHA requirements, the American Heart Association recommends fatty marine sources containing 500 mg or more of EPA and DHA per 3oz cooked serving (e.g., salmon and tuna).   ALA is the most commonly consumed O3FA in the Western diet as it is found in plant-based foods (e.g., dark green leafy vegetables, walnuts, canola oil, flax seed). Unlike EPA and DHA, an Adequate Intake (AI) level is established at 1.6 g/day and 1.1 g/day for men and women respectively.

The Final Verdict 

The wide range of benefits stemming from marine O3FAs indicates the importance of regular consumption of fatty seafood and EPA and DHA-containing products.  The incorporation of plant-derived ALA may serve more importantly as a substitute for omega-6 fatty acids to reduce bodily inflammation, decrease the high O3FA:O6FA ratio typically observed in the Western diet, and to help elevate EPA and DHA levels in the body. EPA and DHA may be featured as the health promoting “dynamic duo,” but ALA is still invited to the party!

 

References

1.         Yanni Papanikolaou JB, Carroll Reider and Victor L Fulgoni. U.S. adults are not meeting recommended levels for fish and omega-3 fatty acid intake: results of an analysis using observational data from NHANES 2003–2008. Nutrition Journal 2014.

2.         Harris WS, Mozaffarian D, Lefevre M, Toner CD, Colombo J, Cunnane SC, Holden JM, Klurfeld DM, Morris MC, Whelan J. Towards establishing dietary reference intakes for eicosapentaenoic and docosahexaenoic acids. J Nutr 2009;139(4):804S-19S. doi: 10.3945/jn.108.101329.

3.         Frits A. J. Muskiet MRF, Anne Schaafsma, E. Rudy Boersma and Michael A. Crawford. Is Docosahexaenoic Acid (DHA) Essential? Lessons from DHA Status Regulation, Our Ancient Diet, Epidemiology and Randomized Controlled Trials. Journal of nutrition 2004;134.

4.         Mozaffarian D, Wu JH. (n-3) fatty acids and cardiovascular health: are effects of EPA and DHA shared or complementary? J Nutr 2012;142(3):614S-25S. doi: 10.3945/jn.111.149633.

5.         Bork CS, Veno SK, Lundbye-Christensen S, Jakobsen MU, Tjonneland A, Schmidt EB, Overvad K. Dietary Intake of Alpha-Linolenic Acid Is Not Appreciably Associated with the Risk of Ischemic Stroke among Middle-Aged Danish Men and Women. J Nutr 2018. doi: 10.1093/jn/nxy056.

6.         Evangeline Mantzioris MJJ, Robert A Gibson and Leslie G Cleland Differences exist in the relationships between dietary linoleic and alpha-linolenic acids and their respective long-chain metabolites. Am J Clin Nutr 1995;61:320-4.

7.         Agriculture. USDoHaHSaUSDo. 2015 – 2020 Dietary Guidelines for Americans. 8th Edition. December 2015.