Category Archives: Diet and Nutrition

Right Fats, Right Amounts

Fats (a.k.a. lipids) are organic substances that are not soluble in water. They win the prize for the most energy dense macronutrient. Whereas protein and carbohydrates deliver 4 calories per gram, fats serve up 9 calories per gram. For this reason, many diets argue for severely restricting (or eliminating) fats from the daily meal plan to speed weight loss. Beyond the challenge of sustaining a fat-free diet, such constraints ignore the essential work that fats do for our bodies. They serve as:

  • Building blocks for cell membranes as well as several hormones and hormone-like substances
  • Nutrient sources for brain development
  • Thermal insulation for vital organs
  • Carriers for fat-soluble vitamins (A, D, E, and K)
  • Appetite suppressors by slowing digestion and conferring a sense of fullness

When folks consume too little fat, they may experience low energy, difficulty concentrating, depression, weight gain, and mineral deficiencies. They may also wonder why their food doesn’t taste very good!

fatsFats come in several forms:

Saturated fats show all available carbon bonds filled by hydrogen atoms; there are no double carbon bonds. They are solid or semi-solid at room temperature – e.g., animal fats, cheese, coconut oil, palm oil. Saturated fats form 50% of cell membranes, support calcium absorption into bones, protect the liver from toxins, enhance immune function, and provide an antimicrobial shield around the heart. They’re the most stable fat; they don’t go rancid even when used at high heat for cooking. The body can make them from available carbohydrates if they’re not included in the diet.

Monosaturated fats have one double-bond of carbon atoms. They are liquid at room temperature and relatively stable. They’re found in olive oil as well as almonds, peanuts, pecans, cashews, and avocados. They are considered heart-healthy fats when used in moderation. The body can make them from saturated fats if they’re not included in the diet.

Polyunsaturated fats have two or more double carbon bonds – e.g., omega-3 and omega-6. The body cannot make these fats; they must be obtained from foods. We need omega-3 fats to produce hormone-like compounds called prostaglandins which play a role in reproduction as well as resolving inflammation. They’re found in oils of cold water fish (e.g., herring, shell fish, sardines) and flaxseeds. Omega-6 fatty acids are found in vegetable oils (e.g., corn, safflower, sunflower) and support proper functioning of cells. Polyunsaturated fats are fragile in that they tend to become oxidized or rancid when subject to heat, air, light, and/or moisture. That’s why they’re packaged in dark bottles and may require refrigeration. When they’ve gone bad, they become extremely reactive chemically and may cause damage to cell membranes, blood vessels, and red blood cells.

Trans fats are unsaturated fats that have been hydrogenated artificially to preserve shelf life and sustain high temperatures in commercial fryers. They’re also inexpensive. Unfortunately, they raise bad (LDL) cholesterol levels and lower good (HDL) cholesterol levels. Eating trans fats increases the risk of developing heart disease, stroke, and type 2 diabetes.

Most fat in the body takes the form of triglycerides – i.e., three fatty-acid chains attached to a glycerol molecule. While elevated triglycerides are a risk factor for heart disease, they don’t come from food directly. We make them in the liver as a function of excess sugars that have not been used for energy.

Cholesterol has been characterized as a lipid even though it does not contain a fatty acid. It gives cell membranes stiffness and stability and is essential for corticosteroids (stress hormones), sex hormones, bile salts, and serotonin receptors. There’s no dietary requirement to consume cholesterol because the body can make all that it needs. Ingesting dietary sources of cholesterol may not raise blood serum cholesterol (although excess consumption is hardly recommended!) Elevated serum cholesterol may be associated with a thyroid condition or the presence of high levels of altered, free radical-containing fats from which cholesterol serves a protective function.

Nutritionist Roberta Anding suggests that a prudent diet contains no more than 30% dietary fat of which 70-80% is unsaturated. Eating plans with < 20% dietary fat have been associated with lower rates of cancer and cardiovascular disease. She advises that we be careful with eating fish due to mercury contamination. Above all, eliminate processed or deep-fried foods containing trans fats or free-radical-containing unsaturated oils as they’re more likely to behave like marauders than nutrients.

Eat the Right Carbs

All plants produce carbohydrates – sugar and starch. Through cooking, chewing, and enzymatic action during digestion, these substances transform into glucose molecules that the body uses for energy. When consumed in their whole, unrefined states, carbohydrate-rich foods contribute life-sustaining vitamins, minerals, enzymes, protein, fat, and fiber. They also moderate the speed at which glucose enters the bloodstream.

Like any finely tuned machine, our bodies want a steady supply of fuel to function at peak efficiency. They don’t want to be inundated with more than they can handle any more than they want to run dry. When we eat sugars and starches in their natural states alongside healthy protein and fat, they’re digested slowly, and the resulting sugars enter the bloodstream at a measured pace over a period of hours. The body gets exactly what it needs, when it needs it.

When we eat processed foods, sugars enter the bloodstream in a rush. The body kicks insulin and related hormone production into high gear to get rid of the excess. Excess insulin may work a little too well, plunging blood sugar lower than its desired state. The resulting hunger pangs may trigger further consumption of processed foods, which starts that negative spiral all over again. Eventually, the body stops responding to insulin and accumulates an unhealthy level of sugar in the bloodstream, a condition known as diabetes. And because processed foods lack the vitamins, minerals, fiber, et al associated with whole foods, the body must deplete its nutrient reserves to sustain life and/or suffer the ill effects of nutrient deficiencies.

We exacerbate our processed foods sugar rush with direct consumption of sugars and syrups. Sugar used to be a luxury item whose delights were experienced sparingly. In 1700, inhabitants of the developed world consumed a mere 4 pounds of sugar per person per annum. By 1800, this figure rose to 18 pounds and topped 60 pounds by 1900. According to the USDA, 123.2 pounds per person of caloric sweeteners were available for consumption by U.S. consumers in 2019, down from a high of 151.5 pounds in 1999. Excessive consumption of sugar has been associated with a gaggle of adverse health conditions, including cardiovascular disease, diabetes, kidney disease, liver disease, obesity, bone loss, and dental decay.

Unfortunately, carbohydrates have been tarred with the ill-effects of processed foods and sugars to the extent that so-called dietary gurus started promoting high-protein, low-carbohydrate meal plans as the way forward. This approach fails to acknowledge the crucial metabolic functions that carbohydrates provide. They deliver the fuel necessary to maintain our metabolism and keep us moving. They prevent ketosis, a physiological state in which there is an excess of ketones in the blood or urine (caused when fat is not burned appropriately). And, by attending to the body’s energy needs, they free protein to perform its life-sustaining functions. (Read last week’s post.)

carbohydratesIn a well-balanced diet, at least 50% of one’s daily calories should come from carbohydrates, according to nutritionist Roberta Anding. These carbs ought to take the form of whole foods – fresh fruits and vegetables, whole grains, legumes, and nuts and seeds (sparingly due to high fat content).

Aim for carbs that have a low glycemic index. The glycemic index measures how quickly your blood sugar rises after consumption of food. A high number indicates rapid conversion to sugar; a low number suggests a slow rise in blood sugar. Carbohydrates with a high glycemic index present the greatest risk of chronic disease when consumed in quantity.

Foods with a low glycemic index include:

  • Fruits: apples, berries, oranges, lemons, limes, grapefruit
  • Non-starchy vegetables: broccoli, cauliflower, carrots, spinach, tomatoes
  • Whole grains: quinoa, couscous, barley, buckwheat, oats
  • Legumes: lentils, black beans, chickpeas, kidney beans

Food with a high glycemic index include:

  • Bread: white bread, bagels, pita pockets
  • Rice: white rice, jasmine rice, arborio rice (i.e., the rice used in risotto)
  • Cereals: instant oats, breakfast cereals
  • Pasta and noodles: lasagna, spaghetti, ravioli, macaroni, fettuccine
  • Starchy vegetables: mashed potatoes, potatoes, french fries
  • Baked goods: cake, doughnuts, cookies, croissants, muffins
  • Snacks: crackers, microwave popcorn, chips, pretzels
  • Sugar-sweetened beverages: soda, fruit juice, sports drinks

Protein: The Body’s Build and Repair Squad

Americans give a great deal of thought to protein. Grocers and health food stores serve up a wide variety of protein drinks, protein powders, and protein bars. Several weight loss “experts” tout the benefits of high-protein, low-carbohydrate diets. Elite athletes credit protein for their impressive musculature. But is protein really worth all that fuss?

proteinWithout a doubt, we could not survive without protein. Our bodies build a wide variety of proteins using amino acids per instructions encoded in our DNA. There are nine essential amino acids which must be included daily in the foods we eat. Our bodies can manufacture the remaining eleven nonessential amino acids should they be absent from our diets.

Protein’s primary function is to build and repair tissue. This role takes on elevated importance during periods of rapid growth, intense exercise, and recovery from injury or surgery. Protein also supports immune function, synthesizes enzymes, acts as a chemical messenger, serves as a transport mechanism, and maintains fluid balance by preventing leakage in the space between cells. In a pinch, protein can provide a source of energy if the body lacks sufficient carbohydrates for the tasks at hand. However, nutrition expert Roberta Anding likens this usage to burning $100 bills in a fireplace to heat a room. It’ll take care of business but reflects a really poor use of resource.

Our bodies need daily deposits of amino acids; we don’t store them. Beef, poultry, fish, dairy products, and soy have been deemed “complete proteins” as they serve up adequate quantities of all nine essential amino acids. Folks who pursue a whole food plant based diet get the requisite quantity of essential amino acids eating a variety of complementary foods – e.g., rice and beans, peanut butter and whole wheat bread. Such foods need to be eaten over the course of a day; they don’t have to be combined at every meal.

So, how much protein do we need?

The Daily Reference Intake (DRI) for a normal adult’s daily protein intake is .8 grams per kilogram of body weight, or .36 grams per pound. That figure translates into 54 grams of protein for the average 150-pound adult. According to Anding, endurance athletes need 1.2-1.4 grams of protein per kilogram of body weight (g/Kg) per day, and strength-training athletes need 1.6-1.8 g/Kg per day. Infants and adolescents also need elevated protein intake: 2 g/Kg daily for infants, and 1 g/Kg daily for adolescents.

How much protein are we getting?

According to a survey by the American Journal of Clinical Nutrition, our average daily protein intake came to 56+14 grams in young children, 91+22 grams in adults, and 66+7 grams in the elderly. Unfortunately, excess protein does not translate into elevated function. If eaten in lieu of carbohydrates, it creates inefficiency in the production of energy. If it simply amounts to  excess daily calories, it contributes to weight gain.

According to Dr. T. Colin Campbell, if you are a “normal” adult and follow a balanced whole food plant based diet, you will get the right amount of protein in a form that is least disruptive to the body’s controlled alkaline blood serum. If, on the other hand, you like being an omnivore, take a lesson from the world’s longest-lived human beings. Consider limiting your intake of meat, poultry, fish, eggs, and dairy to 10% or less of daily calories.

Drink Water!

When we think about nourishing our bodies, most of us fixate on the foods we eat. Which diet should I follow? Which will give me the right balance of protein, carbohydrates, and fat? Should I take supplements and, if so, which ones? Amidst all this musing, we give little thought to an incredibly important element of our daily intake: WATER.

As adults, we are all roughly 50-70% water by weight. Water is the primary component of all body parts and plays a major role in numerous life-sustaining functions. According to the “rule of threes,” we can survive only 3 minutes without breathable air, 3 days without drinkable water, and 3 weeks without food.

So, what does water do for us?

glass of waterWater produces saliva that begins the breakdown of foods in our mouths. Drinking water before, during, and after a meal supports healthy digestion. It also gives the stomach a means to register fullness, thereby moderating the impulse to overeat.

Water helps dissolve vitamins, minerals, and other nutrients from our food. It uses the bloodstream to transport these nutrients to every cell in our bodies. It keeps our cell membranes moist and provides the means for them to grow, reproduce, and thrive. It also helps our skin look its best.

Water helps excrete waste from our systems through sweat, urination, and bowel movements. Appropriate water intake is protective against urinary tract infections, kidney stones, and hemorrhoids. And when we consume the recommended daily dose of fiber to feed our good gut bacteria, adequate water ensures that all this roughage doesn’t turn to “concrete” on its way out of our systems!

Water lubricates our joints and cushions sensitive tissues in our spinal cords and brains. It’s the body’s built-in shock absorber. The brain also uses water to manufacture hormones and neurotransmitters.

Water regulates our internal body temperature through sweat and respiration. And since breath is naturally humidified, we expel water even when our bodies chug along at the optimal temperature.

How much water do we need?

The U.S. National Academies of Sciences, Engineering, and Medicine deems an adequate daily fluid intake to be 15.5 cups for men and 11.5 cups for women. These recommendations account for water from all sources – water, other beverages, and food. As such, the “rule of thumb” of consuming eight 8-ounce glasses of water per day should generally do the trick.

Water intake needs to increase if living in a hot, humid climate or exercising strenuously to account for the body’s water loss via sweat to lower body temperature. Airplane travel can lead to dehydration due to the dry cabin air. You also need to drink more water if feverish or subject to fluid loss through vomit or diarrhea.

Note: For each pound of body weight lost in exercise, you need to rehydrate with 16-24 ounces of fluid. A high quality sports drink helps replenish fluid and electrolytes while providing a source of calories for fuel.

How do I know if I’m getting the right amount of water?

Check out the color of your urine first thing in the morning. If you are adequately hydrated, it will look like pale lemonade. If there’s very little discharge or it looks like apple juice, it’s time to pour yourself a tall glass of water! Other signs of dehydration include unexpected weight loss, confusion, dry skin that’s hot to the touch, and elevated core body temperature.

Note: There’s a lag time between the onset of dehydration and thirst. If you are thirsty, you are already running low on fluids.

Is it possible to drink too much fluid?

The gastrointestinal track can only handle 1-2 liters of water at a time. Flood your system with fluids and your kidneys can’t keep up with the deluge. The resulting overhydration dilutes sodium in the blood – a condition called hyponatremia – which could lead to a life-threatening medical emergency, such as cerebral edema.

Renewed Focus on Nutrition

For me, the start of a new year always tees up the opportunity to launch self-improvement initiatives. Diet and nutrition head this year’s list. Though I’ve read and have written quite a bit about the subject, there’s always more to learn. My guide for the next several posts will be Roberta H. Anding, MS, RD/LD, CSSD, CDE, Assistant Professor at the Baylor College of Medicine and a clinical dietician with over 30 years’ experience. She teaches an outstanding course entitled Nutrition Made Clear on Great Courses Plus (a.k.a., Wondrium).

What is this topic so important?

As a nation, we’re becoming increasingly unhealthy. According to the Centers for Disease Control, the majority of Americans are either overweight (i.e., their Body Mass Index or BMI ranges between 25 and 30) or obese (i.e., their BMI exceeds 30)… and the trend data are not heading in a favorable direction.

us trend data on body mass index

Excess body fat has been linked to elevated risk for heart disease, stroke, type 2 diabetes, certain types of cancer, osteoarthritis, sleep apnea, and clinical depression. Beyond the deleterious effects on the individual, these conditions result in staggeringly high medical costs.

So how did we get here?

The simple answer: We eat too much food and too much of the wrong kinds of foods.

average daily per capita calories

We’ve gotten the message. According to Pew Research, 54% of us believe that we’re paying closer attention to healthy eating that we did 20 years ago; however, 58% of us think we should eat healthier most days. Mintel’s research tells us why:

  • 43% of Americans believe that it’s difficult to be healthy given our modern lifestyle
  • 80% believe healthy living demands sacrifice
  • 40% find the health information landscape confusing

That last point bears closer examination. There is SO MUCH information about diet and nutrition out there. BusinessWire reports that the U.S. weight loss market is now worth $72 billion. That’s a whole lot of financial incentive to promulgate dietary information that may or may not reflect hard science. Anding raises warning flags for:

  • Promises of quick and effective cure-alls
  • Claims of miraculous breakthroughs, secret formulas, and treatments
  • Bamboozling medical terminology
  • Attempts to equate “all natural” with safety and efficacy
  • Aggressive use of personal testimonials
  • An artifice of scarcity – e.g., “limited supply,” “act now”
  • Money-back guarantees

In short, if it’s too good to be true, it probably isn’t true.

There’s no substitute for going back to basics – i.e., eating a balanced diet of whole, unprocessed foods in the right amounts consistently. While it takes a bit more investment in time, I’ve learned to multi-task while preparing meals – e.g., watching TV while doing food prep, or listening to an audiobook or podcast while cooking. I’ve found ways to make healthy meals taste really good. (Just ask my husband!) And I watch portion size.

If you’d like high quality information, Anding recommends the following resources:

To that list, I would add www.NutritionFacts.org. I’ve been watching Dr. Michael Greger’s short videos for years and consistently find them well-constructed, newsworthy, and evidence-based.

The Trouble with Beef

cattle

Climate change has emerged as a “hot topic” in recent Presidential elections. Green-leaning candidates leverage the increased frequency and severity of weather incidents as proof sources that our planet is becoming increasingly less healthy. Most promote “clean energy” and call for reduced emissions from motor vehicles. According to the National Center for Biotechnology Information (NCBI), they should also promote increased consumption of plant-based foods to reduce our impact on the environment.

The NCBI sounded alarm bells on the global livestock industry years ago. Here are some troublesome facts as presented in a report entitled Reducing the Environmental Impact of Dietary Choice:

  • Our global community uses 30% of its land to raise livestock. Deforestation to support animal habitats reduces biodiversity (on which human life depends) and negatively impacts freshwater supplies by increasing runoff.
  • We use 70% of our global agricultural land to produce livestock feed – typically corn, soybean meal, and grains. These crops consume millions of pounds of pesticide and billions of pounds of fertilizer.
  • It takes 11 times more fossil fuel and 100 times more water to produce protein from meat than an equivalent amount of vegetable-based protein.
  • Livestock accounts for 18% of total greenhouse emissions which include nitrous oxide, methane, carbon dioxide, and ammonia.
  • Livestock consume 8% of freshwater directly and thwart groundwater replenishment through soil compaction and degradation to the banks of waterways.
  • A vegan diet was determined to have the lowest environmental impact.

The Environmental Working Group’ report entitled Meat Eater’s Guide to Climate Change and Health doubled down on the environmental perils of meat consumption:

  • Lamb, beef, and cheese production generates the highest emissions. (Since beef produces milk and cheese, we need to cut back on those products as well as steaks, ribs, ground beef, et al.)
  • Beef generates more than twice the emissions of pork, nearly four times that of chicken, and more than 13 times that of vegetable proteins such as beans, lentils, and tofu.
  • In the U.S. alone, livestock generated three times the amount of manure (waste) as humans. While in theory it could be used as fertilizer, in practice it tends to simply pile up and pollute.
  • As of 2009, confined feeding operations have been responsible for damaging water supplies associated with 34,000 miles of rivers and 216,000 acres of lakes and reservoirs. (No doubt today’s figures would be even more eye-popping!)
  • Slaughterhouses dump vast quantities of pollutants into our waterways which contaminate our drinking water, kill fish, and create “dead zones.”
  • Widespread use of antibiotics on livestock promotes the development of resistant strains that threaten human life. Antibiotics prove necessary to minimize disease in overcrowded spaces. (As a side benefit, they promote growth, thereby improving profit margins.)
  • If everyone in the United States ate no cheese or meat once a week over the course of a year, it would have the equivalent impact of taking 7.6 million cars off the road.

Even though these findings call for us to reduce meat eating drastically, our dietary patterns are moving in the opposite direction. The NCBI reports that worldwide meat consumption tripled between 1971 and 2010 during which our population grew by only eighty-one percent.

If we take environmental scientists at their word, we cannot sustain our current eating habits. They exacerbate global warming, needlessly contribute to the degradation of the environment, and deplete nonrenewable resources. Given the eminent threat of food and water shortages, it makes no sense to stay this course.

When it costs so little, why not take the plunge and shift some or all the daily menu to more environmentally sensitive choices?

The Trouble with Chicken

chickens

Chicken used to play a big role in our meal planning. We regularly ate eggs for breakfast, opted for chicken atop our lunchtime salads, and featured chicken most nights for dinner. When I started reading up on diet and nutrition a few years ago, we made the switch to a predominantly whole food plant based diet. So, chicken has fallen out of favor in our household. As it turns out, chicken has also fallen out of favor with epidemiologists and environmentalists, too.

According to the Pew Environmental Group,1 chicken is the most popular meat in America. In the forty years between 1970 and 2010, we doubled our per capita chicken consumption (to 84 pounds annually) while expanding the US population by ~50%. The poultry industry responded by gearing up production and finding ways to bring their products to market at lower cost for producers and consumers. Their key strategy: economies of scale.

Sentience Institute’s US factory farming estimates suggest that we raise 99% of our meat chickens and 98% of our egg-laying chickens in concentrated animal feeding operations (CAFOs).2 For chickens, the USDA defines a CAFO as an operation in which 125,000 meat chickens or 82,000 eggs chickens are confined for over 45 days per year. Breeding and specialized feed have enabled chickens to reach their full weight in just 6-7 weeks.

Conditions within factory farms are rather grim. There’s no fresh air or natural sunlight. The animals live beak-to-beak atop their droppings, breathing the ammonia fumes from all their waste. Overcrowding brings on stress which dampens their immune systems and elevates aggressive behavior. (My first case study in business school examined the practically of fitting chickens with blurry contact lenses so they’d be less successful in their attacks on other birds.) A lack of exercise and excess weight puts strain on their muscular-skeletal systems which may give rise to suffering.

If your compassion for chicken life has not been aroused, perhaps your concern for human life might be. According to Dr. Michael Greger,3 these environments are breeding grounds for the frightening emergence of supervirus strains. Hundreds of individuals were infected by the Avian influenza (H5N1) in 1997 for which there was a 50% fatality rate. The 2002 SARS-CoV outbreak claimed 774 victims among 8098 cases, or a 9.5% fatality rate. The 2012 MERS-CoV outbreak claimed 858 deaths among 2499 laboratory-confirmed cases, or a 34.3% fatality rate. These outbreaks were subject to rapid containment because the afflicted parties presented clear manifestations of illness. We have not been so fortunate with COVID-19. Though its fatality rate is far lower than other CoV strains to date, its ease of transmission and prevalence of asymptomatic carriers presents substantial hurdles for containment.

Dr. Greger warns that the worst may be yet to come. An H7N9 virus has managed to jump from poultry to humans, killing 616 of the 1568 infected. While it hasn’t yet acquired the capacity to transmit from human to human, animal factories may present an opportunity for mutation that would activate a human type receptor. If so, the results could be devastating in loss of lives, disruption to supply chains that support life, and massive economic losses.

Even if we were to turn a blind eye to our exposure to deadly viral agents, we should acknowledge the environmental risks posed by CAFOs. Pew Environmental Group tells us that these operations produce an enormous amount of waste that cannot be used productively for cropland nutrients. The excess washes off the land and into local streams, rivers, and other bodies of water. The resultant algae overgrowth creates a hostile environment for fish and other marine life, often creating “dead zones.”

While advocacy groups and regulators are busy figuring out how to adjust factory farming standards to mitigate risk to human and environmental health, there are two simple practices that we can adopt to reverse these unsettling trends:

  • Reduce the demand for poultry by reducing the amount that we consume. (I rarely eat chicken or turkey these days and don’t miss it at all.)
  • Purchase free-range poultry from farmers who raise their animals humanely and safely. (You can generally find these folks at local farmers’ markets.)

References:

1https://www.pewtrusts.org/-/media/legacy/uploadedfiles/peg/publications/report/pegbigchickenjuly2011pdf.pdf
2https://www.sentienceinstitute.org/us-factory-farming-estimates
3https://nutritionfacts.org/video/the-covid-19-pandemic-may-just-be-a-dress-rehearsal/

Whole Food Plant Based Diet Boosts Immune Function

covid-19This week’s reporting on COVID-19 tells us that over 1.5 million US residents have tested positive for the disease and over 90,000 have been confirmed to have died from it. Such figures fail to count those who have not presented symptoms sufficient to warrant testing nor those whose deaths fell outside the net of COVID-19 tracking. The elderly and those who are immunocompromised represent a disproportionate percent of deaths. And there is no end in sight.

As a member of a household with above-average risk of severe infection, I’m paying close attention to actions we can take to help our bodies prepare for the “fight of their lives” should it come to it. A prime focus centers on our diet. Here’s why…

Scientists tell us that the COVID-19 virus enters the body principally through the nose and mouth; it uses lung tissue as its initial breeding ground. So, the first line of defense against the invader must be the mucosal membranes of the oral cavity and respiratory tracts. These membranes fight infection by secreting Type A antibodies (called secretary immunoglobulin A or SIgA). According to a study published by the University of Western Sydney, we can boost our SIgA response by consuming mushrooms. Healthy volunteers who added one cup of mushrooms to their daily diet showed 50% more Type A antibody secretion than the control group. [See Note 1.]

Should a virus break through mucosal membrane fortification, the body’s innate and adaptive immune responses go into action. Our innate immune response avails itself of natural killer cells that target pathogens, including viruses responsible for common respiratory infections. The adaptive immune response designs and produces antibodies that are custom-tailored to combat specific invaders. For proper functioning, the adaptive response must be sufficiently nimble to ramp up production during the window of opportunity in which the infection can be contained without going on overdrive and recklessly attacking its own vital tissues.

I used to think that the immune system was something that was genetically pre-determined. You either had a good one, or you didn’t. But it turns out that its functioning has a great deal to do with the quality of the microbiome in our intestinal tract. As discussed in a prior post, the microbiome plays an active role in digestion, vitamin and amino acid production, and metabolic regulation. With advancing technology, scientists can now trace the extent to which the microbiota and immune system work symbiotically to provide for the body’s response to microbial threat and maintenance of overall health. [See Note 2.] In short, a well-functioning microbiome provides the means for favorable gene expression and serves a crucial role in immune homeostasis. To that end, we must pay close attention to what we eat.

vegan dietHere are a handful of evidence-based recommendations:

Eat 5-7 servings of fruits and vegetables daily. While immune function tends to decline in older adults, one study considered the possibility that older adults are simply getting too few servings of fruits and vegetables daily. It traced the efficacy of vaccine-induced antibody response in two groups of older adults: one ate 5 or more servings of fruits and vegetables daily, and the other only 2. The former demonstrated a 2.5x boost in immune response versus the latter. [See Note 3.] Word to the wise: Eat a colorful assortment of produce to maximize phytonutrient diversity and make your meals interesting.

Make sure your diet includes plenty of fiber. Undigested complex carbohydrates elevate production of short-chain fatty acids (SCFAs) that serve as energy sources for the gut microbiota and intestinal epithelial cells. Epithelial cells serve as gatekeepers that permit absorption of healthy substances into the body and block entrance to harmful ones. To that end, load up on whole grains, legumes, fruits, and vegetables.

Add immune-boosting superstars to your diet, notably mushrooms, bitter greens, garlic, green tea, and kiwifruit.

Add a tablespoon of ground flax seeds to your daily regimen. They’re loaded with anti-inflammatory omega-3 fatty acids and aid in the absorption of fat-soluble vitamins like A, D and E, all of which are crucial for immune health.

Avoid highly processed and fried foods as they increase inflammation, deplete nutrients, and dampen immune response.

Finally, a study published through the CUNY School of Public Health explored the health advantages of a strict vegan diet over vegetarian or healthy omnivore alternatives. [See Note 4.] It found that the vegan microbiota showed reduced levels of resident microbes with pathogenic potential and a greater abundance of protective species. The vegan microbiota was also associated with reduced inflammation and lowered the risk of arteriosclerosis.

Notes:

  1. https://nutritionfacts.org/video/boosting-immunity-while-reducing-inflammation/
  2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5541232/
  3. https://nutritionfacts.org/video/boosting-immunity-through-diet/
  4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4245565/

Harvard Weighs in on Nutrition

I just finished reading an article1 about Dr. Frank Hu, professor of nutrition and epidemiology at the Harvard T.H. Chan School of Public Health. He and his colleagues created the following Healthy Eating Plate based on the best available scientific evidence:

healthy eating plate

Vegetables: Eat lots of them – the greater the variety the better. Potatoes, French fries, and tater tots don’t count.

Fruits: Eat plenty of fruits of all colors.

Whole Grains: Eat a variety of whole grains; limit refined grains (e.g., white rice, white bread).

Healthy Protein: Choose fish, poultry, beans, and nuts; limit red meat and cheese. Avoid bacon, cold cuts, and processed meats.

Water: Drink water, tea, of coffee with little to no sugar. Limit milk/dairy and juice. Avoid sugary drinks.

Healthy Oils: Use modest amounts of olive oil or canola oil for cooking and in salads, as needed. Limit butter. Avoid trans fats.

Unlike the U.S. Government’s Eating Plat, the Harvard version does not have a specific provision for dairy, and it places far greater emphasis on vegetables.

Dr. Hu and his colleagues are as concerned about our health as they are the health of the planet (which are, of course, inexorably intertwined). According to the article, food production accounts for 80% of deforestation, 70% of fresh water use, and 30% of human-generated greenhouse gas (GHG) emissions. Meat and dairy production account for 80% of the food industry’s GHG. Moreover, it takes 11 times more fossil fuels to produce a single unit of animal protein than it takes to produce a comparable amount of grain-based protein.

If eating meat were deemed healthy, there’d be a painful trade-off between bolstering human health and bearing the environmental cost. But it turns out that meat isn’t that healthy. Findings from the 2012 Health Professionals Follow-Up Study and Nurses’ Health Study revealed that increasing one’s consumption of meat by a single serving per day elevates morbidity risk by 13-20%.

Hu has published several papers on plant-based diets but claims that it does not have to be vegan or vegetarian. As I’ve read elsewhere, meat as a condiment instead of prominent occupant of the plate seems to be alright (though processed meats are not good!)

Hu and his colleagues face an uphill battle in gaining governmental traction on their recommendations. Powerful political and commercial interests stand in their way. And, to be sure, there are still randomized, double-blind studies to be done to solidify their research. But as Hu says: “Globally, if we always just wait for the absolute proof or conclusive evidence, then it’s going to be disastrous. It’s going to be too late for both human health and the environment.”

 

1 See Diet Science: Healthy Humans, Healthy Planet by Jacob Sweet in Harvard Magazine, March-April 2020

Daily “Tricks” to Support Weight Loss

hints and tipsIn my final post on Dr. Michael Greger’s How Not to Diet: The Groundbreaking Science of Healthy, Permanent Weight Loss, I’ll cover the a few “tweaks” that he recommends to optimize a diet for weight loss. (He advises a consult with your doctor if you have any medical conditions or have difficulty with any of these recommendations.)

At Each Meal:

  1. Drink 1-2 glasses of cool or cold water before eating.
  2. Start each meal with “negative calorie” foods – e.g., an apple, a very light soup, or salad
  3. Flavor meals (or a glass of water) with 2 teaspoons vinegar.
  4. Focus on eating, not the TV, notepad, or smartphone.
  5. Decrease bite size and eat slowly to allow for the 20 minutes necessary for your brain to catch up with your stomach.

Every day:

  1. Take in 1/4 teaspoon black cumin powder.
  2. Use 1/4 teaspoon garlic powder.
  3. Use 1 teaspoon ground ginger or 1/2 teaspoon cayenne pepper.
  4. Eat 2 tablespoons nutritional yeast. (When pre-packaged, it’s usually near the spice section. Otherwise, check out the bulk foods section.)
  5. Take 1/2 teaspoon cumin with lunch and dinner.
  6. Drink water, black coffee, or hibiscus tea during meals. Drink 3 cups of green tea daily between meals, waiting at least an hour after you finish eating.
  7. Drink a glass of water hourly, fitting in at least 8 cups throughout the day.
  8. Eat whole (intact) grains to make your microbiome happy. Flour doesn’t count.
  9. Have your largest meals earlier in the day. Eat breakfast like a king, lunch like a prince, and dinner like a pauper.
  10. Confine your meals to a 12 hour window – e.g., 7:00am to 7:00pm.
  11. Exercise 90 minutes daily. (For optimal results, wait 6 hours after your last meal – e.g., first thing in the morning.)
  12. Weigh yourself regularly.
  13. Work on establishing good habits (and breaking old ones) with a set of intentions – e.g., when I sit down to watch TV, I’ll drink a glass of water and work on a Sudoku puzzle to break the habit of snacking mindlessly. Take stock daily on how you’re doing. Adjust your list every 2 months.

Every night:

  1. Fast after 7:00pm.
  2. Get a good night’s sleep!

If any of these recommendations seems peculiar, I have a suggestion for you. Get a copy of Dr. Greger’s book and read it cover to cover! As I’d mentioned in the introductory post to this series, he provides nearly 5,000 citations of credible (vetted) scientific evidence for each one of his recommendations. And by investing the time to read this amazing book, it’ll help you reinforce your commitment to a healthier you!