I’m often asked what I consider to be the healthiest diet. Through decades of nutritional research and experimentation, I’m convinced that a diet of primarily organic, plant-based Mediterranean foods—including whole grains, fruits, vegetables, nuts, legumes, eggs, dairy products (cow, goat and sheep milk derived) and healthy fats (mostly olive oil), with fish and seafood playing a key role as a main protein source—is by far the best diet for long term health. The term “pesca-flexa-vegetarian” comes closest to describing the diet that my family and I eat.
Many people today define their diet based on what they don’t eat: “gluten-free,” “low-carb,” or “low-fat” are among the most popular regimens. But I believe we create healthier eating habits if we focus on what we do eat, rather than on what we don’t eat. For instance, it’s possible to be a vegetarian or pescatarian while eating a diet that’s very unhealthy, full of processed starches and sugars, junk foods and fish sticks, instead of a healthier diet based on whole foods.
I believe people have more misconceptions about food than perhaps anything else related to health. These misconceptions lead to dietary fads that are often needlessly restrictive, unbalanced, and even detrimental. When I ask people where they get their information, the most common answer I receive is, “I read it on the internet.” The internet is a wonderful resource, and it can also be dangerously misleading. The simple truth is that the internet is not a reliable source for factual information.
Dietary fads are not based on good science. For example, I commonly hear, “I am on a grain-free diet because grains make you fat and cause dementia.” The truth is that whole grains are highly nutritious and have the least carbon footprint of any food group. Based on meta-analysis research studies, eating whole grains is associated with healthy weight, reduced chronic disease, and lower mortality.
The Many Health Benefits of Whole Grains
Research shows that whole grains are positively correlated with increased lifespan. Two recent studies1 examined data from millions of people in more than four dozen different studies, and found evidence showing those who eat the most whole grains have a number of reduced health risks compared to those eating the least, including:
- Reduction of death from all causes (down 16% in one, 18% in the other)
- Reduction of death from heart disease (down 18% in one, 21% in the other)
- Reduction of death from diabetes (down 36% in one, not studied in the other)
- Reduced risk of heart disease (down 22%) or cancer (down 15%)
Additional studies indicate similar findings:
- Reduction of cardiovascular disease 2,3
- Inhibition of colon and other cancers 4,5
- Enhancement of gut microbiota and aid in immune and inflammation regulation 6
Why I Choose a Pescatarian Diet
I’ve long been intrigued by the relationship of diet and health, and have studied nutrition extensively for forty years, beginning in 1977 when I worked in a natural food store in Stamford, CT. It was also in 1977 when I had my last bite of meat, much to the consternation of my Italian mother, who didn’t understand my desire to explore different ways of eating. In the ensuing years, I’ve experimented with veganism, a 100% raw foods diet, and lacto-ovo vegetarianism.
I’ve settled on a “pesca-flexi-vegetarian” diet, which expands on a broad based lacto-ovo vegetarian diet to include fish, which I enjoy almost daily. This diet most closely resembles a traditional Mediterranean diet, which research shows—and I’m convinced—is the most healthful diet. Just to be clear, I have no problem with people eating meat on occasion. In many traditional cultures, meat was enjoyed as a celebratory food, such as a “feast” to honor a special day or occasion.
There are several reasons why I choose to include fish and seafood in my diet:
1) Health Benefits
We know that eating fish is good for you. In fact, fish, along with many fruits, vegetables, legumes and whole grains, are some of the ultimate “healthy aging” and “health-promoting” super-foods.
Fish in general—and fresh sardines and anchovies, in particular—play an important role in the diets of many peoples known for their longevity, including the inhabitants of the Greek islands of Crete and Icaria, as well as Sardinia, an island off the coast of Italy. There are many proven benefits to plant-based diets, including a lower risk of obesity and chronic diseases like heart disease and diabetes as well as cancer. 7-12
- Weight Control. According to research, you can get many of the same protective benefits from a pescatarian diet. One study found that women who were pescatarians gained 2.5 fewer pounds each year than women who ate meat.10 And people who shifted their diet in a more plant-based direction gained the least amount of weight, indicating that reducing your animal consumption may be good for you no matter what your current eating patterns are.
- Heart Health. Research shows that pescatarians have a lower risk of developing diabetes (4.8%), compared to omnivores (7.6%) (8). Additionally, one large study looked at people who ate meat rarely or were pescatarians. They had a 22% lower risk of dying from heart disease compared to meat-eaters.9
- Cancer Prevention. Recently, a prospective study looked at associations between survival outcomes and fish and omega-3 fatty acid intake after a colon cancer diagnosis. The study included 1,011 stage III colon cancer patients who were part of an adjuvant chemotherapy trial, and found that patients who consumed dark meat fish at least twice per month had longer recurrence-free survival, disease-free survival, and overall survival compared with those who consumed no fish. In patients with COX2 tumor expression, omega-3 fatty acid was associated with improved disease-free survival.11
2) Environmental Concerns
Raising livestock comes at a high environmental cost. According to the United Nations, raising livestock contributes to 15% of all human-made carbon emissions. In contrast, producing fish and seafood has a lower carbon footprint than producing any type of animal meat or cheese.
The production of animal-based foods in general, but meat for consumption specifically, is associated with significantly higher greenhouse gas (GHG) emissions than plant-based foods. Studies show that GHG emissions in kilograms of carbon dioxide equivalents per day are 7.19 for high meat-eaters ( > = 100 g/d), 5.63 for medium meat-eaters (50-99 g/d), 4.67 for low meat-eaters ( < 50 g/d), 3.91 for fish-eaters, 3.81 for vegetarians and 2.89 for vegans. In conclusion, dietary GHG emissions in meat-eaters are approximately twice as high as those in vegans. It is likely that reductions in meat consumption could be the number one best way to reduce GHG emissions in the world.13
Unique Nutritional Benefits of Fish
Fish is the best dietary source of vitamin D, which many people are deficient in. Studies show that pescatarians tend to have higher levels of vitamin D than vegetarians.14
Seafood is also an important source of omega-3 fatty acids, essential nutrients that have numerous health benefits. Two unique omega-3 fatty acids found in fish are EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Omega-3 fatty acids are found in every kind of fish, but are especially high in fatty fish. Some good choices are wild caught salmon, trout, sardines, herring, mussels, and oysters.
Omega-fatty acids from fish have been shown to:
- Protect cardiovascular health by lowering blood pressure and reducing the risk of heart attack, abnormal heart rhythms, and strokes.
- Enhance healthy brain and nervous system function, decreasing the risk of depression, ADHD, Alzheimer’s disease, and dementia.
- Help calm inflammation, protecting against arthritis and other inflammatory diseases.
- Play an important role in visual and neurological development in infants.
The Healthiest Fish to Eat
Pacific Northwest salmon is one of the best of all fish to eat. Besides being a good source of protein, particularly the muscle building amino acid “proline,” salmon is an excellent source of omega-3 fatty acids and vitamin D. Salmon is also rich in astaxanthin, a unique and important carotenoid responsible for the pink/orange color of salmon (as well as trout and shrimp). Astaxanthin is a carotenoid that does not convert to vitamin A and is a powerful “redox-antioxidant,” acting as a potent oxygen enhancer and single oxygen quencher protecting against free radical damage. I suggest consuming only wild caught salmon from the Pacific Northwest or Alaska.
A caution about eating fish—consuming the wrong kinds of fish too often can increase the level of mercury stored in your body. It’s important to be aware of the best (lowest in mercury) fish to eat, as well as the amounts that are safe to consume. I advise everyone to avoid fish known to contain high amounts of mercury, especially pregnant women and nursing mothers, because mercury can cause neurological damage to a fetus or newborn. Young children and pregnant or nursing women should only consume fish with the lowest mercury content. The chart below is a helpful guide:
Lessons From the Blue Zones: Beyond Diet
I’m firmly convinced that a pesca-flexi-tarian diet is the most well rounded, satisfying, and health-promoting diet that we can eat, and there’s plenty of research to support this.15 But while diet is a cornerstone of a healthy lifestyle, there are many other factors that are also necessary for a healthy and satisfying life.
Since the 1990s, researchers have been studying areas in the world where people routinely enjoy long life spans. Scientists have deemed these special areas as “Blue Zones.” Here are nine lessons on healthy living from the Blue Zones:
- Physical Activity.Don’t do marathons or pump iron; work around the house, garden, walk, cycle, do yoga or swim.
- Know your purpose.Have a reason for waking up in the morning.
- Kick back.Find ways to shed stress, whether it’s praying, mediating, relaxing, or hanging out with friends and family.
- Eat less.Stop eating when you are 80% full.
- Eat less meat.Beans are a cornerstone of most centenarians’ diets.
- Drink alcohol in moderation.Only the Seventh-day Adventists in California don’t drink alcohol; all other Blue Zone populations enjoy alcohol in moderation, generally one to two glasses of wine daily.
- Embrace Theology and Faith.Attend faith-based services, believe in God and live in accordance with religion based in love.
- Power of love.Put family first, including commitment to a partner and keeping aging parents and grandparents nearby.
- Stay social.Build a social network that supports healthy behaviors.
- Whole Grain Value Live Longer with Whole Grains, June 22, 2016; http://wholegrainscouncil.org/node/22948/print, retrieved June 26, 2016.
- Wan Z, Qin J, Qin Whole-grain intake and total, cardiovascular, and cancer mortality: a systematic review and meta-analysis of prospective studies; Chen G, Tong X, Xu J,
- Han S, L; American Journal of Clinical Nutrition (May 2016)
- Seal CJ, Nugent AP, Tee ES, Thielecke F. Whole-grain dietary recommendations: the need for a unified global approach, Br J Nutr. 2016 Jun;115(11):2031-8. doi: 10.1017/S0007114516001161. Epub 2016 Apr 15.
- Mehta R, Nishihara R, Cao Y, Song M, Mima K, Qian Z, Nowak J, Kosumi K, Hamada T, Masugi Y, Bullman S, Drew D, Kostic A, Fung T, Garrett W, Huttenhower 6) C, Wu K, Meyerhardt J, Zhang X, Willett W, Giovannucci E, Fuchs C, Chan A, Ogino S; Association of Dietary Patterns With Risk of Colorectal Cancer Subtypes Classified by Fusobacterium Nucleatum in Tumor Tissue; JAMA Oncology (Jan 2017)
- Vanegas SM, Meydani M, Barnett JB, Goldin B, Kane A, Rasmussen H, Brown C, Vangay P, Knights D, Jonnalagadda S, Koecher K, Karl JP, Thomas M, Dolnikowski G, Li L, Saltzman E, Wu D, Meydani SN. Substituting whole grains for refined grains in a 6-wk randomized trial has a modest effect on gut microbiota and immune and inflammatory markers of healthy adults. Am J Clin Nutr. 2017 Mar;105(3):635-650.
- Orlich MJ1, Singh PN, Sabaté J, Jaceldo-Siegl K, Fan J, Knutsen S, Beeson WL, Fraser GE. Vegetarian dietary patterns and mortality in Adventist Health Study 2, JAMA Intern Med. 2013 Jul 8;173(13):1230-8. doi: 10.1001/jamainternmed.2013.6473.
- Tonstad S1, Butler T, Yan R, Fraser GE. Type of vegetarian diet, body weight, and prevalence of type 2 diabetes, Diabetes Care. 2009 May;32(5):791-6. doi: 10.2337/dc08-1886. Epub 2009 Apr 7.
- Key TJ1, Fraser GE, Thorogood M, Appleby PN, Beral V, Reeves G, Burr ML, Chang-Claude J, Frentzel-Beyme R, Kuzma JW, Mann J, McPherson K. Mortality in vegetarians and non-vegetarians: a collaborative analysis of 8300 deaths among 76,000 men and women in five prospective studies, Public Health Nutr.1998 Mar;1(1):33-41.
- Rosell M1, Appleby P, Spencer E, Key T. Weight gain over 5 years in 21,966 meat-eating, fish-eating, vegetarian, and vegan men and women in EPIC-Oxford. Int J Obes (Lond).2006 Sep;30(9):1389-96. Epub 2006 Mar 14.
- Key TJ, Appleby PN, Rosell MS. Health effects of vegetarian and vegan diets, Proc Nutr Soc.2006 Feb;65(1):35-41.
- Peter Scarborough, Paul N. Appleby, Anja Mizdrak, Adam D. M. Briggs, Ruth C. Travis, Kathryn E. Bradbury, and Timothy J. Key, Dietary greenhouse gas emissions of meat-eaters, fish-eaters, vegetarians and vegans in the UK, Clim Change. 2014; 125(2): 179–192. Published online 2014 Jun 11. doi: 1007/s10584-014-1169-1.
- Crowe FL1,Steur M,Allen NE, Appleby PN, Travis RC, Key TJ.Plasma concentrations of 25-hydroxyvitamin D in meat eaters, fish eaters, vegetarians and vegans: results from the EPIC-Oxford study, Public Health Nutr. 2011 Feb;14(2):340-6. doi: 10.1017/S1368980010002454. Epub 2010 Sep 21.
- Derbyshire EJ, Flexitarian Diets and Health: A Review of the Evidence-Based Literature, Front Nutr.2017 Jan 6;3:55. doi: 10.3389/fnut.2016.00055. eCollection 2016.