Paleo Diet: What It Excludes, the Trial Evidence and What It Takes Off an Indian Plate

The paleo diet, short for Palaeolithic, is built on foods its authors believe were eaten before farming: lean meat, fish, eggs, vegetables, fruit, roots and nuts. It excludes grains, pulses, dairy, added sugar, added salt and processed food. The trials behind it are few, small and short; a 2015 systematic review found only four, with 159 participants between them. On an Indian plate it removes roti, rice, dal and curd together, the foods that supply about two thirds of the energy in ICMR-NIN's model day. This entry belongs to NNWA's handbook of diets.

What does the paleo diet allow and exclude?

The lists vary a little between books and trials, but the core is stable. The Swedish trials that began the research described the diet as based on lean meat, fish, fruits, vegetables, root vegetables, eggs and nuts. A 2019 meta-analysis adds what is avoided: grains, dairy products, processed foods, added sugar and added salt. An Australian trial that followed a popular paleo book also barred legumes, corn and white potatoes, allowed small amounts of olive or coconut oil, and replaced milk with unsweetened almond milk.

Read the table from an Indian kitchen and the difficulty is plain. A vegetarian is left with vegetables, fruit, nuts and, if they are eaten, eggs. Dal, curd and paneer, the main vegetarian protein foods, all sit in the excluded rows. The diet was designed around meat and fish, and it has no vegetarian form that the trials have tested.

What did the paleo trials find?

Short-term improvements in waist, weight and some blood markers, measured against diets based on national guidelines. The 2015 review in the American Journal of Clinical Nutrition pooled four randomised trials in people with at least one feature of metabolic syndrome. At six months or earlier, the paleo groups had a waist 2.38 cm smaller and triglycerides 0.40 mmol/L lower than the comparison groups. A 2019 meta-analysis of eight trials reported 2.17 kg more weight loss and a waist 2.90 cm smaller.

Notice what the comparison was. Each trial set paleo against a guideline-style diet, usually without matching energy intake, and the paleo groups ate less. In the 2009 crossover trial the paleo diet was lower in total energy, energy density and carbohydrate, so part of the result is simply a smaller, less processed diet. The handbook's entry on the low-carbohydrate diet covers what cutting carbohydrate does on its own.

How strong is the evidence?

Weak to moderate for a few months, and close to absent after that. The 2015 reviewers rated their evidence as moderate, but it rested on 159 people. The 2019 authors found that their results for blood lipids, blood pressure and C-reactive protein changed when single studies were removed, and wrote that the evidence is not conclusive. The American Diabetes Association's 2019 consensus report describes the paleo studies in type 2 diabetes as small and few, with 13 to 29 participants, lasting no longer than three months, and mixed in their effects.

The one long trial is the most useful. Seventy obese postmenopausal women in Sweden were assigned to a paleo-type diet or to the Nordic recommendations for two years. Fat loss was greater on paleo at six months, but the difference was no longer significant at 24 months, and the authors noted that adherence to the protein target was poor. No trial has measured heart attacks, fractures or deaths, and none found for this entry was run in India or on Indian food.

Paleo on an Indian plate: roti, rice, dal and curd removed

ICMR-NIN's Dietary Guidelines for Indians set out a model day of 2,000 kcal, the My Plate for the Day, with the grams and the share of energy from each food group. Three of its groups are excluded on paleo. Adding up their rows shows how much of the day has to be rebuilt from meat, fish, eggs, nuts, vegetables and fruit.

The non-vegetarian model day is hit almost as hard: cereals at 45 per cent of energy, pulses at 9 and milk at 11 come to 65 per cent, and the 70 g of chicken, meat or eggs it already includes supplies only 5 per cent. A paleo eater in India therefore has to multiply the meat, fish and egg portion several times over, which raises the cost of the plate and moves it away from the pattern the guideline describes.

Which nutrients run short without dal, roti and curd?

Calcium first, then iodine, some B vitamins and folate. In the Australian trial, women on paleo ate 355 mg of calcium a day after four weeks, down from 771 mg, against an Indian adult allowance of 1,000 mg. Their intakes of thiamine, riboflavin and iodine fell as well, and the authors called for research on the long-term effect of so large a fall in calcium. The Swedish diabetes trial also found the paleo diet lower in calcium.

On Indian food the arithmetic is similar. Whole cow's milk holds 118 mg of calcium per 100 g in the Indian Food Composition Tables, so the 300 ml of milk or curd in the model day gives about 354 mg, and paneer holds 476 mg per 100 g. Ragi, at 364 mg per 100 g, is a grain and is excluded too. Among pulses, rajma carries 316 mcg of folate per 100 g and chana dal 182 mcg. The calcium table for Indian foods and the handbook's entry on calcium give the full picture.

Iodine needs a separate note. The adult allowance is 150 mcg a day, and ICMR-NIN asks households to use iodised salt to meet it. A diet that avoids added salt and dairy removes the usual sources at once; in the Australian trial, iodine intake was 47.9 mcg a day lower on paleo than on the comparison diet, though the authors caution that food records measure salt poorly.

An Indian day on the paleo diet

The day below shows what paleo looks like with food from an Indian market. It is an illustration, not a recommendation, and it is non-vegetarian because the diet leaves little choice. Raw weights are this page's assumptions. Worked from the Indian Food Composition Tables, the day supplies about 370 mg of calcium, a little over a third of the 1,000 mg allowance.

The fresh vegetables, whole fruit, nuts and fish, and the absence of sweets and packaged snacks, agree with the Indian guidelines. The rest is exclusion. The Indian food calorie counter shows how much of a normal day's energy comes from the staples being removed.

A worked example: a vegetarian weighing up paleo

This is an illustrative case, not a real person. Take a 34-year-old analyst in Bengaluru who is vegetarian, eats eggs now and then, and wants to lose a few kilograms. A colleague has recommended paleo. She uses ICMR-NIN's vegetarian model day as her starting plate and works out what the rules would cost.

Common myths and mistakes

The second mistake is to read paleo as permission for unlimited meat. The trials specified lean meat and fish with plenty of vegetables and fruit. The cohort analysis in The Lancet Public Health, which pooled 432,179 participants, found mortality 18 per cent higher where carbohydrate was exchanged for animal fat and protein from sources such as lamb, beef, pork and chicken. Observational data cannot prove cause, but it is the only long-term evidence there is.

Who should not follow paleo, and who needs a doctor first?

If you take insulin or tablets that lower blood glucose, see your doctor before starting. Paleo cuts carbohydrate sharply as a side effect: in the Australian trial the paleo group's carbohydrate was lower by 14.6 per cent of energy than the comparison group's. The American Diabetes Association's report warns that plans very low in carbohydrate can reduce blood glucose swiftly and that a practitioner must review insulin and other glucose-lowering medicines to prevent hypoglycaemia. Never change a dose yourself.

People with kidney disease should not adopt a meat-heavy diet without medical advice; ICMR-NIN states that high protein intake may worsen kidney function in those who already have renal disease. Adolescents need calcium-rich foods such as milk, milk products and ragi to reach peak bone mass, by the same guidelines, so paleo does not suit them or younger children. Pregnant and breastfeeding women, older adults at risk of weak bones, and anyone with a history of disordered eating should stay with a balanced plate unless their own doctor advises otherwise.

It does not suit vegetarians either, for the reasons the worked example shows. NNWA's guide to vegetarian protein sources explains how dal, curd, paneer and soya meet the need that paleo would leave open.

Is paleo better than other diets for weight loss?

There is no good evidence that it is. The pooled advantage over guideline diets was about 2 kg in trials lasting weeks to months, and the single two-year trial found the difference in fat mass no longer significant at the end. Paleo has not been tested head to head over years against patterns with far larger evidence behind them, such as the DASH diet or the Mediterranean diet. NNWA's Weight Management course teaches how to plan weight loss for healthy adults without excluding whole food groups.

Learning this with NNWA

Judging a diet against its evidence is part of NNWA's Diploma in Nutrition. The academy is a private skill institute in Kolkata teaching online, in English and in Hindi. Its learners are prepared to guide healthy clients and to hand medical cases to a doctor. Nothing it teaches is a degree, and nothing it awards is a dietitian qualification.