Vegan Diet: An honest audit
No animal products — plants, legumes, grains, optionally fortified foods
6/10
Sustainability
6/10
Short term
6/10
Long term
Three numbers, one rubric
Category
Restrictive
Typical cost
~$180/mo
First visible change
~28 days
Evidence rating
Moderate evidence
Studies cited
3
How to read these scores
Sustainability
Weighted heaviest. Adherence predicts outcome more reliably than macro split, so an approach nobody can keep scores low here even when the trial data looks good.
Short-term effect
A high number here alone means very little. Water and glycogen move fast, and almost every restrictive protocol looks impressive at week four.
Long-term effect
Where short-term and long-term diverge sharply, you are usually looking at a regain mechanism built into the design — not a willpower failure.
What it promises — and how it says it works
The claim
What it claims
Vegan diets exclude all animal products. Health-driven proponents (Greger, Esselstyn, Ornish) claim vegan eating reverses heart disease, prevents cancer, and produces optimal health. Whole-food plant-based (WFPB) is the strongest version; UPF-vegan (Beyond Burgers, Oreos, processed foods) is metabolically very different.
The mechanism
How it is supposed to work
Whole-food vegan is high-fibre, high-polyphenol, low-saturated-fat, high-volume per calorie. It naturally limits UPF if practised well, and shares much of the Mediterranean pattern's benefits. UPF-vegan inherits all the issues of UPF generally — a vegan Pop-Tart is metabolically a Pop-Tart.
What the research actually shows
Adventist Health Study and EPIC-Oxford suggest vegan/vegetarian diets are associated with lower cardiovascular events and modestly lower all-cause mortality, though confounding by lifestyle (less smoking, more exercise) is hard to separate. Ornish's reversal-of-CHD trial (1990) used a comprehensive lifestyle intervention including vegetarian diet, exercise, stress reduction. Long-term vegan adherence requires attention to B12 (mandatory supplementation), iron, zinc, omega-3 (DHA), iodine, calcium, and protein quality.¹²³
Footnote numbers link to the full reference list at the foot of this page.
Evidence rating
Moderate evidence
Describes the quality and quantity of the peer-reviewed literature — trial count, duration, sample size and replication — not our opinion of the approach.
Early loss is not evidence. Glycogen carries roughly three grams of water per gram, so the first pounds on almost any restrictive protocol are largely water. What matters is what is still there at twelve and twenty-four months.
Right person, wrong person
Almost nothing on this site is universally good or universally useless. The useful question is which body, kitchen and calendar an approach was built for.
Worth a trial
Who it works for
Adults with strong ethical commitment, those who genuinely enjoy plant-heavy meals, adults with cardiovascular disease who benefit from the most extreme plant-based form. Adults who want to reduce environmental impact of food.
Look elsewhere
Who it fails
Adults who think 'vegan' means healthy by default and end up eating UPF-vegan junk. Athletes who don't pay attention to protein quality and quantity. Adults with iron-deficiency anaemia history who don't supplement properly. Children without careful planning.
Whole-food plant-based eating is one of the strongest evidence-based dietary patterns for cardiovascular health. UPF-vegan is metabolically poor regardless of ethics. Adequate vegan eating requires deliberate planning around B12, omega-3, iron, zinc, and protein. If you commit to WFPB with proper supplementation, the long-term outcomes are excellent. If you're 'plant-based' on Beyond Burgers and Oreos, you've achieved the ethics goal but not the health goal.
Written against the rubric, not against a sponsor. Individual response varies and no outcome is guaranteed.
What to do instead
If health (not ethics) is the driver: Mediterranean captures most of WFPB's benefit with fewer adherence issues. If ethics: WFPB with planned supplementation.
Not sure which fits
Get a read on your profile
Fifteen questions, roughly two minutes, no email wall on the result. Returns a starter protocol matched to your metabolic situation.
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Straight answers
Vegan Diet, without the spin
We score Vegan Diet 6/10 for sustainability, 6/10 for short-term effect and 6/10 for long-term effect. A gap between the short-term and long-term numbers is the single most common pattern in this index — an approach can move the scale quickly and still leave almost nothing behind eighteen months later.
Sustainability is weighted heaviest for a reason: across head-to-head trials, adherence predicts outcome more reliably than which named diet you picked. A protocol you abandon in week six did nothing at all.
Can you still be doing this in month twelve?
First 12 weeks in controlled trials
What survives at 12–24 months
Educational summaries of published research. Individual response varies and no outcome is guaranteed.
References
- 01Estruch R et al. (2018). Primary Prevention of Cardiovascular Disease with a Mediterranean Diet Supplemented with Extra-Virgin Olive Oil or Nuts (PREDIMED). New England Journal of Medicine. PubMed 29897866
- 02Lane MM et al. (2024). Ultra-processed food exposure and adverse health outcomes: umbrella review of epidemiological meta-analyses. BMJ. PubMed 38418082
- 03Valdes AM et al. (2018). Role of the gut microbiota in nutrition and health. BMJ. PubMed 29899036
Did Vegan Diet not work for you?
That is the rule rather than the exception, and it is usually a design problem in the protocol rather than a character problem in you. The assessment reads your situation and points you at the approach the research supports for that profile.
- Free, with no email wall on the result
- Fifteen questions, roughly two minutes
- Returns a starter protocol matched to your profile
- Every recommendation links back to its research
Educational only, not medical advice. This audit summarises published research and is not a diagnosis, a prescription, or a treatment plan. Consult your physician before major dietary changes or altering prescribed medication. These statements have not been evaluated by the Food and Drug Administration. Individual results vary; no outcome is guaranteed.