Jeff Nelson

What Jeff says, topic by topic

Vitamin B12

In a February 2020 video Nelson, then vegan for about 24 years, said he had stopped taking B12 about a year earlier, and reviewed studies linking high blood levels of the vitamin to problems including cancer¹.

A month later he said viewers had misread that video: he had never told vegans to stop, and he does recommend that vegans take B12². He explained that a test the previous May had shown his level far above the range after years of supplements, which is why he paused for seven or eight months³. His level then fell more than he expected, and he said he was resuming 500 mcg two or three times a week and would test again⁴. His advice was to test now and then, to avoid being either too low or too high⁵.

What all the experts say about vitamin B12

Vitamin D

In a 2018 video Nelson said he does not take vitamin D, and that from his reading it is unnecessary except for a small group of people with specific problems⁶.

In the same video he faulted a NutritionFacts video on falls as out of date, noting that the US Preventive Services Task Force recommended in April 2018 against vitamin D for preventing falls in older adults living at home⁷. Of a review of 56 trials cited for longer life, he said its own authors cautioned that it should not be used to promote supplements as a way to live longer⁸.

What all the experts say about vitamin D

Omega-3 fats

In a long 2019 video, introducing himself as a health journalist rather than a doctor or dietitian, Nelson concluded that nobody living a healthy lifestyle needs DHA supplements, vegan or not, and advised against omega-3 blood tests⁹. He asked anyone weighing DHA to consider studies suggesting the supplements may raise cancer risk in men¹⁰.

He said a healthy whole-food diet supplies the omega-3 people need, with a tablespoon of ground flaxseed for anyone concerned¹¹. To help the body convert plant omega-3 into EPA and DHA, he favoured a low-fat diet that limits foods high in fat and omega-6¹².

A 2026 VegSource video kept the same line, calling warnings that vegans risk dementia without DHA fear marketing built on weak science, while saying it was not claiming the supplements cause dementia¹³.

What all the experts say about omega-3 fats

Oil

Weighing in on a 2025 olive oil debate between Rip Esselstyn and Garth Davis, Nelson said each helps people in his own way, but that for reversing disease and reaching optimal health he stays in the oil-free camp¹⁴. He tied his view to his family: his wife Sabrina and his father recovered their health on a version of the Esselstyn and McDougall program¹⁵.

In another 2025 video he doubted claims that flax oil causes weight loss, noting that oils carry 9 calories per gram against 4 for carbohydrate and protein, which makes them the most calorie-dense food¹⁶. He suggested any weight lost could come from digestive upset and poor absorption¹⁷.

In 2026 VegSource took on the idea that salads need added fat. The video granted that fat raises blood carotenoids for some hours after a meal¹⁸, but asked where the healthy vegans are who lose vitamin A, or their sight, because they skipped the oil¹⁹.

What all the experts say about oil

Protein

A 2025 VegSource video answered a channel that warned of a new protein shortfall in vegans. It said the study behind the warning, of about 193 long-term vegans in New Zealand, found that about half met lysine and leucine targets once digestibility was counted, yet no one was ill²⁰. It added that the official allowances are padded by design and that most people eat about double²¹.

What all the experts say about protein

Calcium, dairy and bones

In his 2019 series on nut research, Nelson called a dairy-funded analysis of the PURE study rigged: it compared poor people in poor countries, who ate little meat or dairy and had scant medical care, with wealthier neighbours who could afford both food and doctors, so any link favouring dairy was built in²².

What all the experts say about calcium, dairy and bones

Calorie density

In a 2016 video on Walter Kempner’s rice diet, Nelson said that for weight loss McDougall relies on calorie density: choosing less calorie-dense foods and eating them until full²³.

What all the experts say about calorie density

Nuts, seeds and avocado

In a 2018 video series on nuts Nelson said anyone may eat nuts but should not believe the hype, and that people with heart disease should probably avoid or limit them²⁴. He said he rarely eats them himself because he would eat far too many²⁵.

In the series’ second part, in 2019, he argued that much nut research is commercial, paid for by groups such as the California almond commission and the International Tree Nut association²⁶²⁷.

A 2026 VegSource video revisited a NutritionFacts claim that nuts do not cause weight gain. It said that 14 of the 18 cholesterol trials cited were built to hold calories and body weight steady, so they could not test the claim²⁸.

What all the experts say about nuts, seeds and avocado

Salt

In a 2026 video on blood pressure, Nelson said salt matters but is only half the story, and passed on Peter Rogers’ view that the balance of potassium to sodium may count for more than sodium alone²⁹. He repeated McDougall’s rule of keeping salt out of the cooking and adding a light sprinkle at the table, if that helps someone stay on a plant-based diet³⁰.

His own 2024 day of eating showed the same care: he compared sauces by their sodium, rejecting one with about 250 mg a serving³¹, and rinsed canned chickpeas to wash off as much sodium as he could³².

What all the experts say about salt

Sugar

In the 2016 video Nelson said Kempner’s rice diet of white rice, fruit, sugar and juice reversed kidney disease, diabetes and heart disease³³. He noted, though, that in Kempner’s 1975 obesity study the weight loss came on a diet of 400 to 800 calories a day at first, and always under 1,000³⁴.

What all the experts say about sugar

Starches

In a 2026 video Nelson credited McDougall with making the reversal diets livable by putting potatoes, rice, corn, beans and oats at the centre of the plate, so people eat until full without counting³⁵. He added that for most of history people lived on one main staple with vegetables, fruit in season and a little animal food³⁶.

In his 2016 weight-loss video he called starches the source of satisfaction on the plate, with non-starchy vegetables filling a third to a half of it³⁷.

What all the experts say about starches

Fasting

In a 2024 video Nelson described a supervised 10-day fast on water alone at TrueNorth Health, where he lost 15 pounds and kept 10 of them off; his blood pressure fell from 140/80 and settled near 106 to 112 over 65 to 72³⁸. Eight weeks later, he said, his total cholesterol was down 80 points and his LDL down 61³⁹.

He reported that his lipoprotein(a), usually seen as fixed by genes, fell about 40% but stayed high⁴⁰, and that his ApoB moved from 111 into the desirable range at 81⁴¹. Answering worries about muscle loss, he cited a TrueNorth DEXA case report in which a man lost body fat but kept most of his lean tissue⁴².

He said that if a loved one developed a serious health problem he would likely urge a medically supervised water fast, pointing to TrueNorth’s published case reports⁴³.

What all the experts say about fasting

Supplements

In his 2019 DHA video Nelson said people should take no supplements other than B12⁴⁴. He argued that loading the body with single nutrients may crowd out the absorption of others, since nutrients are meant to come from food⁴⁵.

What all the experts say about supplements

Fish and eggs

A 2026 VegSource video on a study linking eggs to lower Alzheimer’s risk called it the wrong question. It said such findings rest on food frequency questionnaires⁴⁶, and that the egg industry pays for this kind of research⁴⁷. It argued the better question is which dietary patterns give the best long-term outcomes⁴⁸.

What all the experts say about fish and eggs

Fiber

In a 2026 video Nelson asked how much of the Portfolio diet’s LDL drop came simply from its daily dose of viscous fiber such as psyllium⁴⁹. He said the low-fat programs had long made the point that soluble fiber lowers cholesterol, and that beans, yams, oats, barley and berries supply it with no powder needed⁵⁰. He warned that in Consumer Lab testing four of nine psyllium products held excessive lead⁵¹.

In another 2026 video he said the real lesson of Denis Burkitt’s African observations was not to buy a fiber supplement but that whole eating patterns track with whole patterns of disease⁵².

What all the experts say about fiber

Fruit

In his 2016 weight-loss video Nelson passed on McDougall’s advice to limit fruit to two pieces a day for fastest weight loss, since fruit runs about 300 calories a pound against about 100 for non-starchy vegetables; those in less of a hurry, he said, could eat more⁵³. In his 2024 day of eating, his snack after lunch was watermelon with chopped dates⁵⁴.

What all the experts say about fruit

Vegetables and greens

In 2019 Nelson rejected the idea that raw vegetables must be eaten with fat to absorb their carotenoids, calling it marketing science from studies funded by a salad dressing maker and the avocado industry⁵⁵. He said chopping or cooking vegetables raises absorption, and that the trials worked only in people first starved of carotenoids for days⁵⁶. A 2026 VegSource video made the same case against adding fat to salads¹⁸.

In a 2026 video on claims that plants are toxic, he granted that goitrogens and oxalates matter in specific conditions but said such mechanisms do not justify avoiding broccoli or greens⁵⁷. He noted that people who eat more fruit and vegetables tend to have lower mortality, while cautioning that this is observational⁵⁸.

What all the experts say about vegetables and greens

Beans and lentils

In a 2026 video Nelson agreed that raw or undercooked kidney beans carry a lectin that can make people ill⁵⁹, but said cooking inactivates it, and that nobody has shown that properly prepared beans eaten normally harm health⁶⁰. Beans appeared in both main meals of his own 2024 day of eating, home-cooked or canned and rinsed⁶¹³².

What all the experts say about beans and lentils

Whole grains, bread and flour

In his 2016 weight-loss video Nelson set aside breads, pastas, bagels and other flour products, saying flour is absorbed faster and raises insulin more than intact grains; corn tortillas were the exception he allowed⁶². In a 2026 video he again favoured intact foods over flour products for people trying to lose a lot of weight⁶³.

He has argued that the grains Americans added after 1970 were mostly refined⁶⁴⁶⁵. His own 2024 meals were built on parboiled basmati rice⁶⁶.

What all the experts say about whole grains, bread and flour

Potatoes

In a 2026 video Nelson said that plain potatoes, rice and beans taste like cardboard only to a palate trained on rich food; within a short time a baked potato starts to taste sweet, and the potato is among the most filling foods ever tested⁶⁷.

In another 2026 video he agreed that green or sprouted potatoes build up solanine and should not be eaten, but said that says nothing against properly prepared potatoes⁶⁸.

What all the experts say about potatoes

Meat

In a 2026 video Nelson called the turn to meat-heavy diets one more swing of a diet pendulum⁶⁹. He contrasted it with Pritikin, McDougall, Kempner, Esselstyn and Ornish, whose low-fat plant-based programs produced repeatable results in sick patients⁷⁰, and asked where the clinics are that put thousands of patients on meat-heavy diets and reverse chronic disease⁷¹. Humans can survive on many diets, he said, but survival is not the same as optimal health⁷².

In a 2026 video on the Amish, he said he would not take up sausage and gravy just because one Amish farmer lived to 85, any more than he would credit walnuts for a healthy Mediterranean village⁷³.

What all the experts say about meat

Low-fat eating

In a 2026 video Nelson argued that America never actually tried a low-fat diet. CDC surveys showed fat falling as a share of calories, he said, but total calories rose and the grams of fat eaten did not fall⁷⁴. In USDA supply data, added fats and oils were the largest source of the extra calories between 1970 and 2010⁶⁴, with salad and cooking oils more than tripling⁷⁵.

He distinguished between saying the advice to eat less fat backfired, which he called a serious argument, and saying a low-fat diet of beans, oats, potatoes and vegetables failed, which he said was never tested at national scale⁷⁶.

What all the experts say about low-fat eating

Saturated fat

In a 2020 video Nelson argued that unsaturated plant fats are not the cure they are made out to be. He cited a 1969 trial of 846 veterans in which swapping animal fat for plant fat left heart attack and sudden death rates about the same⁷⁷, and agreed with Pritikin that total fat made more difference than the type⁷⁸.

In 2026 he defended Ancel Keys’ Seven Countries study against the charge of cherry-picking⁷⁹. He called the sugar industry’s secret funding of a 1967 Harvard review that blamed fat as bad as it sounds, but said such corruption does not prove saturated fat harmless⁸⁰.

What all the experts say about saturated fat

Cholesterol

In a 2026 video Nelson noted that a meta-analysis of 113 nut trials found LDL fell by only about 5 mg/dL⁸¹, in trials that mostly added nuts to mixed diets with meat, dairy and oil; he said they do not show that people already on a low-fat whole-food diet gain from adding nuts⁸².

In another 2026 video he called the Portfolio diet a legitimate, well-evidenced choice for healthy people who want to lower cholesterol with food⁸³. But he called LDL a proxy, preferring evidence on heart attacks and deaths, and left the statin question to patients and their cardiologists⁸⁴.

Reviewing a former plant-based cardiologist who switched to keto, he pointed out that her LDL rose from 80 to 210 in the same labs she used to fault her old diet⁸⁵.

What all the experts say about cholesterol

Carbohydrates and low-carb diets

In a 2026 video Nelson questioned the story that Americans swapped fat for carbohydrates and got fatter⁸⁶. He noted that sugar availability peaked around 1999 and then fell while obesity kept climbing, and concluded that no single nutrient, sugar, oil, carbs or fat, explains it alone⁸⁷.

He has cited research in which low-fat, higher-carbohydrate plant diets improved insulin sensitivity⁸⁸. Of the cardiologist who blamed carbohydrates and went keto, he said nothing she showed proved that starchy whole foods such as potatoes, beans and grains had caused her insulin resistance⁸⁹.

What all the experts say about carbohydrates and low-carb diets

Coffee, tea and caffeine

In a 2024 video Nelson described how his wife Sabrina was hospitalized in January 2024 with acute liver failure after about a month of drinking a caffeine-free rooibos herbal tea every day⁹⁰. Her tests found no other cause, and a published case report linked rooibos tea to liver injury⁹¹.

He said the problem seems to come from toxic weeds harvested along with some rooibos, called for a warning label, and suggested that frequent rooibos drinkers consider liver tests now and then⁹².

What all the experts say about coffee, tea and caffeine

Chocolate

In a 2019 video Nelson used the chocolate diet hoax, a deliberately weak study that media around the world reported as showing dark chocolate speeds weight loss, as an example of how commercial science markets foods⁹³. In 2026 he mocked chocolate-industry trials claiming that daily dark chocolate does not cause weight gain, as the same flawed reasoning used for nuts⁹⁴.

What all the experts say about chocolate

Mediterranean diet

In a 2026 video Nelson went through the tables of PREDIMED, the trial behind the claim that a Mediterranean diet cuts heart disease by 30%. Both Mediterranean groups ate about 41% of calories from fat and the so-called low-fat group 37%, more than a typical American⁹⁵. The olive oil and nut groups also got free food, donated by industry, and regular counselling, while the control group at first got a leaflet⁹⁶.

He said heart attacks, cardiovascular deaths and total deaths did not differ significantly between groups⁹⁷, and that the 30% figure meant about two percentage points over five years, driven mostly by fewer strokes⁹⁸. He added that the 2013 paper was retracted in 2018 after about one in five participants turned out not to be properly randomized, and the corrected version speaks of association rather than cause⁹⁹.

He stressed that PREDIMED excluded people with known heart disease and never tested a very low-fat diet near 10% fat¹⁰⁰. In another 2026 video he said the Crete and North Karelia stories showed populations lowering risk, not patients reversing established disease¹⁰¹.

What all the experts say about mediterranean diet

Weight loss

In a 2016 video Nelson said he had lost about 30 pounds, from 185 to 155, and cited the American Institute for Cancer Research’s advice to be as lean as possible without being underweight¹⁰²¹⁰³. He put weight gain down to food rather than genes or willpower, citing Terry Shintani’s Hawaii studies in which people ate more food but fewer calories on a traditional low-fat diet and lost weight¹⁰⁴.

His method, he said, came from McDougall’s 1985 maximum weight loss program and calorie density: create a deficit without counting by changing what you eat, not by restricting portions or exercising for hours¹⁰⁵. That meant no animal foods, no oil, no flour products, and no nuts, seeds, avocados, soy foods or olives⁶².

In 2026 he said he had worked on plant-based programs in low-income communities with much obesity, teaching an approach close to McDougall’s that he said takes weight off fast¹⁰⁶.

What all the experts say about weight loss

Cravings and food addiction

In a 2026 video Nelson drew on Doug Lisle’s three drives, seek pleasure, avoid pain and conserve energy, which served people well when food was scarce but now meet food engineered to be hard to stop eating¹⁰⁷. He said we have made unhealthy eating easy, cheap and normal and then blame people for lacking willpower¹⁰⁸.

As with smoking, he argued, the answer is to change the surroundings: keep the problem foods out of the house, make the healthy choice easy, and build a life that does not depend on willpower¹⁰⁹.

What all the experts say about cravings and food addiction

Exercise

In a 2015 video Nelson ranked diet first and exercise a close second¹¹⁰. In a 2024 video, at 68, he said he ran about 25 miles a week and had run eight or ten half marathons, usually finishing in the top three of his age group¹¹¹, and argued it is never too late to get fit, calling fitness the main job for people in their 50s, 60s and 70s¹¹².

He described running five or six days a week, with sprint intervals on two of them, plus calisthenics such as pull-ups most days¹¹³. In another 2024 video he said high-exertion exercise is very good for the heart¹¹⁴.

What all the experts say about exercise

Heart disease

In a 2020 video Nelson answered “absolutely” to whether a low-fat, no-oil plant-based diet reverses heart disease, and reviewed angiograms Caldwell Esselstyn had shown of patients’ arteries opening up¹¹⁵.

In 2026 he separated two questions: cutting a population’s risk, and turning back disease in a patient who already has it¹¹⁶. He said Kempner, Pritikin, Ornish, Esselstyn and McDougall reached much the same plate for patients who had run out of options: starches, vegetables, fruit and legumes, little animal food, very little fat and little or no added oil¹¹⁷. He cited Esselstyn’s report that fewer than 1% of adherent patients had a further cardiac event over nearly four years¹¹⁸.

He was candid about the limits: Ornish’s trial was small, Esselstyn’s series had no control group, and no large randomized trial has compared an oil-free whole-food diet with a Mediterranean one in advanced disease¹¹⁹. He still found the work persuasive because the gains showed up in symptoms, outcomes and angiograms across independent doctors¹²⁰. In another 2026 video he cited Lester Morrison’s study of 100 heart attack survivors, in which 19 of the 50 on a very low-fat diet were alive at 12 years and none of the controls¹²¹.

What all the experts say about heart disease

High blood pressure

In a 2026 video Nelson said his own blood pressure had drifted up a few years earlier and came down after a supervised water-only fast, and that he now checks it about once a month¹²². He called high blood pressure a silent killer that raises the risk of heart attack, stroke, kidney disease and dementia¹²³.

He passed on Peter Rogers’ view that the ratio of potassium to sodium matters a great deal, with whole plant foods naturally high in potassium²⁹. He said traditional peoples such as rural Kenyans and the Tarahumara have little hypertension until they adopt a Western diet, so the food, not the genes, is the factor¹²⁴, and he named excess body fat as another major cause¹²⁵. He told viewers on blood pressure drugs to talk to their doctor, since pressure can fall fast on a healthy diet¹²⁶.

What all the experts say about high blood pressure

Diabetes

In a 2016 video Nelson described the Pima of Arizona, who developed near-universal type 2 diabetes after switching to processed, high-fat foods, while their Tarahumara cousins in Mexico stayed slim on their traditional starch-based diet¹²⁷.

In 2026 he said a cardiologist’s report of insulin resistance after years of plant-based eating was not what research on very low-fat plant diets would predict⁸⁸. He cited Neal Barnard’s randomized trial in type 2 diabetes, where the low-fat vegan group lost more weight and cut more medication¹²⁸, and a type 1 trial at about 10% fat in which insulin needs fell 28%¹²⁹. Analysing her cookbook, he found a median of about 12% of calories from fat, with many recipes far higher, and concluded it was not the very low-fat diet the trials used¹³⁰.

What all the experts say about diabetes

Cancer

In a 2022 video on several well-known vegans diagnosed with cancer, Nelson said a healthy low-fat plant-based diet and lifestyle can lower cancer risk, with no guarantees¹³¹. He faulted Joel Fuhrman’s claim that common cancers are completely avoidable on his diet, suggesting a disclaimer¹³².

Speculating about causes, which he said nobody can know, he pointed to supplements, especially DHA, which he said several unbiased studies tie to higher cancer risk¹³³.

What all the experts say about cancer

Dementia and the brain

In a 2023 video Nelson said there is no scientific support for taking DHA to protect the brain, likening it to carrying a rabbit’s foot¹³⁴. To lower Alzheimer’s risk he listed exercise, which he said has a large body of evidence behind it¹³⁵, a diet rich in fruit, vegetables and fiber with little junk food, mental stimulation and social life¹³⁶.

Drawing on a McDougall article, he presented aluminum exposure as a major suspected cause, calling a 2017 study linking brain aluminum to disease severity a smoking gun, and urged avoiding aluminum cookware, additives and hygiene products¹³⁷. He said no pill or supplement protects against Alzheimer’s¹³⁸.

What all the experts say about dementia and the brain

Longevity and aging

In a 2025 video Nelson said Okinawa is the only blue zone studied with serious science, through the Okinawa Centenarian Study begun in 1975¹³⁹. Elders born before the war, he said, ate a high-starch diet of sweet potatoes, greens, rice and beans, under 10% fat and less than one serving of meat a week¹⁴⁰, while the other blue zones rest on magazine reporting with no dietary surveys or blood work¹⁴¹.

In a second 2025 video he added that even Okinawa’s age records are imperfect, since many were destroyed in the war and a 2010 check in Japan found more than 230,000 supposed centenarians were in fact dead or missing¹⁴². He said the lifestyle patterns, mostly plant-based, very low-fat food, movement and social ties, remain solid either way¹⁴³.

What all the experts say about longevity and aging

Each small number links to its reference at the bottom of the page: the video at the exact second, or the page where it was said.