Liz's Blog for a Healthier, Happier Life

Top 10 Studies From 2021 For a Happy, Healthy 2022

Here are 10 of the most significant nutrition studies from the past year to help you live the happiest, healthiest 2022!

Fermented Foods Are Good for Gut Health

Having a diverse gut microbiome (many different species of microbes living in your gut) appears to be highly protective for your physical and mental health. In a 10-week, randomized controlled trial, healthy adults who increased their consumption of fermented foods to 6 servings daily, saw steady increases in the diversity of their gut microbes, along with decreases in markers of inflammation in the body.  Participants consumed a variety of fermented foods including yogurt, kefir, fermented cottage cheese, kimchi and other fermented vegetables, and kombucha tea.  Researchers called the results “stunning” and an example of how a simple change in diet can remodel the gut microbiome. 

Action Step:  People who live in Asian countries, like Japan and Korea, regularly consume three or more servings of fermented foods each day.  In Western countries, like Canada and the United States, fermented foods are just starting to gain attention.  Make a conscious effort to include more in your diet.  Start with one to two servings daily.  Most people enjoy yogurt.  Kefir (fermented milk) makes a great base for smoothies.  Kombucha is now widely available and is another easy addition to most diets (avoid brands high in added sugar).  Limit your intake of fermented foods that are high in sodium, such as kimchi, sauerkraut, and miso.

P.S.  Be sure to give my “Apple Ginger Green Kefir Smoothie” recipe a try (click here).   It’s delicious!!

Reference:  Wastyk, H., et al.  “Gut-microbiota-targeted diets modulate human immune status.”  Cell. 2021 Aug 5;184(16):4137-4153.e14.


The Impact of Alcohol on Brain Health

Researchers from the University of Oxford conducted one of the largest investigations to-date on the impact of alcohol consumption on brain health.  Using state-of-the-art neuroimaging equipment, brain scans were performed on over 25,000 participants from the UK Biobank Study.  No safe dose of alcohol for brain health was found.  Even at moderate levels of intake, a detrimental impact was seen for almost every part of the brain, including white matter, grey matter, connectivity, and brain volume.  The effects were especially significant for binge drinkers and those with high blood pressure or an unhealthy body weight.  No one type of alcoholic beverage (wine, beer, spirits) was less damaging than another.  Researchers believe it is the ethanol, or alcohol itself, that causes the harm.

Action Step:  While light to moderate alcohol consumption may be protective for heart disease, more and more research questions whether and how much alcohol fits into a healthy diet.  This study shows potential harm to brain health.  Alcohol, especially in higher amounts, also increases the risk of at least 7 different cancers (even moderate amounts can increase the risk of some cancers, like breast cancer).  If you do choose to consume alcohol, limit your intake to no more than one drink daily and enjoy it with a meal.  Although no benefit was seen for wine over other alcoholic beverages in this study, some research supports red wine as the healthiest choice based on the beneficial plant compounds it contains (again, only when consumed in small quantities).  Most important – avoid binge drinking (four drinks for women over a 2-hour period, 5 drinks for men). 

P.S.  The consumption of alcohol has increased significantly for many people during the pandemic.  While this has been an extremely challenging time for all of us, do your best to find healthier ways to cope. 

Reference:  Topiwala, A., et al.  “No safe level of alcohol consumption for brain health: observational cohort study of 25,378 UK Biobank participants.”  medRxiv 2021.05.10.21256931.


Low Omega-3 Intake as Harmful to Health as Smoking

Based on data from the Framingham Offspring Cohort Study, involving over 2,200 participants in their mid-60s and followed for 11 years, researchers concluded that a low intake of omega-3 fats powerfully predicts early death and may shorten lifespan by as much as smoking.  Omega-3 intake was determined by measuring EPA and DHA content of red blood cell membranes.  This measurement is referred to as the Omega-3 Index and is considered one of the most accurate ways to assess omega-3 status.  An optimal Omega-3 Index is 8% or higher, an intermediate Index is between 4% and 8%, and a low Index is below 4%.  Most people in Canada and the United States fall into the low or intermediate category (less than 5% fall into the optimal category!).  In Japan, where seafood consumption is significantly higher, most have an Omega-3 Index greater than 8%, and the expected life span is about five years longer than in North America. 

Action Step:  Omega-3 fats (EPA and DHA) have many health-protective attributes associated with lower disease risk and longer life, including significant anti-inflammatory properties.  Aim for two to three servings of higher fat fish each week, such as salmon, rainbow trout, or sardines.  If you don’t regularly consume fish, consider taking a fish oil supplement containing at least 500 mg of EPA plus DHA combined.  Higher doses may be required for conditions like arthritis and depression. 

Reference: McBurney, M., et al.  “Using an erythrocyte fatty acid fingerprint to predict risk of all-cause mortality: the Framingham Offspring Cohort.” Am J Clin Nutr. 2021 Oct 4;114(4):1447-1454.


Keto Diet Can Result in Dangerously High Cholesterol Levels

What happens when you take 24 young, healthy, normal-weight women and put them on a ketogenic diet for 4 weeks?  In this well-designed, randomized-controlled trial, every woman following the low carb/high fat keto diet saw significant increases in their LDL cholesterol levels.  High levels of LDL cholesterol are highly correlated with the development of heart disease. 

Action Step:  I am not a fan of the keto diet.  It’s extreme, not sustainable for most, and limits foods known to strongly protect health, including legumes, fruits, and whole grains.  If you follow this type of eating plan for any reason, be sure to have your cholesterol levels monitored and focus on foods that contain healthier fats, such as avocadoes, nuts, seeds, extra virgin olive oil, and higher fat fish, like salmon.  Limit foods high in saturated fats, including fatty meats, coconut oil, and butter.  Finally, rather than following a keto diet, consider simply limiting your intake of less healthy carbs, including refined grains, like white bread, and high sugar, nutrient-poor foods, such as sugary drinks and snacks. 

Reference:  Burén, J., et al. “A Ketogenic Low-Carbohydrate High-Fat Diet Increases LDL Cholesterol in Healthy, Young, Normal-Weight Women: A Randomized Controlled Feeding Trial.” Nutrients. 2021 Mar; 13(3): 814.


Keep Drinking Coffee to Lower Your Risk of Disease & Live Longer

Research continues to support coffee as a health-promoting brew.  In a recent meta-analysis involving 26 studies and over 3.7 million participants, regular coffee drinking was linked to a significantly lower risk of heart disease, type 2 diabetes, endometrial cancer, and skin cancer (both melanoma and non-melanoma).  For most disease states, a linear relationship existed – each additional cup of coffee provided further protection from disease.  For heart disease, drinking 3 to 4 cups daily resulted in the largest disease risk reduction, with no further reductions seen with higher amounts.  Researchers concluded that drinking caffeinated coffee has a multitude of health benefits.

Action Step:  If you love a good cup of coffee, enjoy it fully knowing that this beverage, chock full of plant compounds, is also good for you.  Limit your intake to about 3 to 4 cups daily (175 mL/6 oz. per cup).  A large coffee from Starbucks, such as a Grande, counts as almost 3 servings.  Drink your coffee early in the day to ensure the caffeine does not interfere with your sleep. Limit unhealthy additions to your coffee, such as sugar and cream.  Lastly, drink primarily filtered coffee, such as drip and pour-over coffee that passes through a filter (k-cup pods also qualify as they have a paper filter inside the pod).  The filter removes specific oils that otherwise, can increase LDL cholesterol levels.  Examples of unfiltered coffee, include French press, Turkish, and espresso.   Limiting your intake of unfiltered coffee is especially important if you are at high risk for heart disease.  Enjoy your coffee!

Reference:  Di Maso, M., et al.  “Caffeinated Coffee Consumption and Health Outcomes in the US Population: A Dose-Response Meta-Analysis and Estimation of Disease Cases and Deaths Avoided.” Adv Nutr. 2021 Jul 30;12(4):1160-1176.


Vitamin D, Immunity & Protection from COVID-19

Based on a meta-analysis and review of 39 studies, researchers concluded that low levels of vitamin D are associated with a significantly higher risk of COVID-19 infection, severity, and risk of dying.  Vitamin D plays an important role in immunity.  It helps regulate our ability to turn on and off the inflammatory response to an invading organism.  A COVID-19 infection is often accompanied by a very aggressive inflammatory response which can enhance disease severity.

Action Step:  The recommended intake for vitamin D for adults is 600 I.U. daily (800 I.U. daily if over the age of 70).  Many people do not get enough of this important nutrient and would benefit from either taking a multivitamin that contains adequate vitamin D or taking a stand-alone vitamin D supplement.  If you take a stand-alone supplement, do not exceed about 1000 to 2000 I.U. daily.  The recommended upper limit from all sources (food and supplements) is 4000 I.U. daily.

P.S.  A healthy gut microbiome also plays a key role in reducing COVID-19 severity and mortality.  Keep your gut healthy by eating a diverse, plant-rich, fibre-rich, fermented food-rich diet. 

Reference:  Kazemi, A., et al.  “Association of Vitamin D Status with SARS-CoV-2 Infection or COVID-19 Severity: A Systematic Review and Meta-analysis.” Adv Nutr. 2021 Sep; 12(5): 1636–1658.


Nutrient Content of Plant-Based Milks Totally Inconsistent

Plant-based milk alternatives, like oat and almond milk, continue to be all the rage.  Often viewed as equivalent to cow’s milk in nutritional value, many plant-based are low in protein and fortified with varying amounts of calcium, riboflavin, and vitamins A, D, and B12.  In a recent study from the Center for Public Health Nutrition out of the University of Washington, a researcher compared the nutrient composition of 641 plant-based beverages.  Except for soy milks, he found little consistency in nutrient density and content.  His conclusion – there is a need to bring industry-wide nutrient standards to these drinks.

Action Step:  Until standards are put in place, understand that soy milk is generally the best nutritional equivalent to cow’s milk, which is very nutrient dense.  If purchasing other types of milk alternatives, such as oat or almond milk, look for ones that are higher in protein, have nutrient fortification levels comparable to cow’s milk (compare labels), and are not high in added sugar or saturated fat.  This is especially important when plant-based beverages replace dairy products in the diets of children and teens.  

Reference:  Drewnowski, A.  “Plant-based milk alternatives in the USDA Branded Food Products Database would benefit from nutrient density standards.”  Nat Food 2, 567–569 (2021).


Sugary Drinks, Colon Cancer, & Our Kids

Colon cancer is increasingly being diagnosed in younger adults, including those in their 20s, 30s, and 40s.  This rise in early-onset colon cancer (diagnosed prior to age 50) looks to be driven by unhealthy lifestyles, with sugary drinks as a key contributor.  A study involving over 95,000 women looked at beverage intake over the last two decades.  Those who consumed two or more sugar-sweetened drinks daily during adulthood were more than twice as likely to develop this type of cancer.  In a subset of 41,000 women whose beverage habits were studied between 13 to 18 years of age, each serving/day increment of sugar-sweetened beverages was associated with a 32% higher risk.  Sugary drinks appear to increase colon cancer risk by harming the gut microbiome, increasing gut permeability, and promoting cancer cell growth and survival. 

Action Step:  The daily consumption of sugar-sweetened drinks (soft drinks, fruit-flavoured drinks, specialty coffees and teas, sports drinks, energy drinks, etc.) has become normalized in our society.  It is not normal.  These drinks contain excessive amounts of sugar, lack nutrition, and can significantly harm health.  This includes a higher risk of obesity, type 2 diabetes, and colon cancer.  Adolescents and young adults are the highest consumers.  Keep these drinks out of your home and discourage their intake.  Always promote and consume healthier alternatives, including water, milk, and unsweetened tea or coffee.

P.S.  Low fibre intakes and high intakes of processed meats and alcohol are also linked to significantly higher rates of colon cancer.  

Reference:  Hur, J., et al.  “Sugar-sweetened beverage intake in adulthood and adolescence and risk of early-onset colorectal cancer among women.” Gut. 2021 Dec;70(12):2330-2336.


Vegetarians More Likely to Suffer from Depression

Based on a meta-analysis of 13 studies, involving almost 50,000 participants, German researchers determined that following a vegetarian diet may significantly increase your risk of depression.  This is consistent with another meta-analysis published earlier in the year.  Vegans and vegetarians are more likely to have low intakes of nutrients such as vitamin B12, vitamin D, iron, zinc, and long-chain omega-3 fats (EPA and DHA).  A low intake of any of these nutrients can compromise mental health.  Food choice also matters.  In a study from France involving over 90,000 participants, vegetarians with a low intake of legumes and those who excluded more foods from their diets (such as vegans) were at higher risk of depression.  In a study from Australia, vegans and vegetarians who consumed less healthy, plant-based diets (for example, diets higher in ultra-processed foods, including refined grains and sugary snacks and drinks) were more likely to suffer from depression, while those who consumed high quality, plant-based foods were protected.

Action Step:  If you follow a vegetarian or vegan diet, plan carefully and make primarily high-quality food choices – lots of legumes, nuts, seeds, fruits, vegetables, whole grains, and fortified milk-alternatives.  In addition, you will need a daily multivitamin and mineral supplement, along with a vitamin B12 supplement (about 10 to 50 mcg daily) and an omega-3 supplement (consider an algae-based supplement containing at least 500 mg EPA and DHA combined).  Having a dietitian review your diet is also highly recommended. 

Reference:  Ocklenburg, S. and Borawski, J.  “Vegetarian diet and depression scores: A meta-analysis.”  J Affect Disord. 2021 Nov 1;294:813-815.


Less Sodium, Plus More Potassium, Saves Lives

What happens when people, age 60 and older, with a history of stroke or high blood pressure, swap the regular salt in their homes for a salt substitute (part of the sodium is replaced with potassium chloride)?  Over a 5-year period rates of strokes, heart attacks, and death from any cause decrease significantly.  This extremely impressive, randomized-controlled trial, involving over 20,000 participants from 600 different villages in rural China, was one of the largest intervention trials ever completed.  Researchers concluded that decreasing sodium intake with a salt substitute saves lives.

Action Step:  High blood pressure is extremely harmful to health and longevity.  A high sodium intake increases blood pressure, while a high potassium intake helps lower it.  Keep your blood pressure healthy by greatly limiting your intake of ultra-processed foods, fast foods, and restaurant meals.  When grocery shopping, compare food labels, and choose less salty options.  Some foods, such as bread, may not taste salty, but can still be a major source of sodium in the diet.  Load up on foods rich in potassium, including legumes, dark leafy greens, broccoli, brussels sprouts, squash, potatoes, sweet potatoes, artichokes, avocadoes, tomatoes, bananas, and cantaloupe.  Finally, try a salt substitute, like Morton Lite Salt (potassium-sodium mix), for all cooking and food preparation in the home. 

P.S.  Learning to cook with lots of herbs and spices is another great way to reduce your sodium intake and powerfully boost your health.    

Reference:  Neal, B., et al.  “Effect of Salt Substitution on Cardiovascular Events and Death.”  N Engl J Med. 2021 Sep 16;385(12):1067-1077.

Here’s to a happy, healthy 2022!!

P.S.  If you enjoyed this article, please share it with your friends.  Thanks!!



I’m a registered dietitian with a passion for peanut butter sandwiches and an undying love for chocolate. I’ve been researching, writing, and speaking about eating for optimal health for over 25 years. I have two wonderful daughters, love hiking year-round, and have a definite addiction to pickleball. Perhaps, most importantly, I never let a good dance song go to waste!

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