10-Day Sugar Detox: What Mark Hyman's Plan Involves and What Works

Originally published 2016-01-10.

A "10-day sugar detox" usually means one thing: for ten days you stop eating added sugar, sweeteners and refined flour, and you build your meals around protein, healthy fats and non-starchy vegetables. The best-known version comes from Mark Hyman's 2014 book The Blood Sugar Solution 10-Day Detox Diet. The plan can be a helpful reset for cravings and eating habits. What it cannot do is "detox" your body, which your liver and kidneys already handle, or guarantee that headaches, pain or body fat will vanish in ten days.

Below is what the plan asks you to do, which parts are backed by good evidence, which claims go too far, and how to try a lower-sugar ten days sensibly.

How much sugar we actually eat

Viral articles often say the average American eats 150 pounds of sugar a year. That figure comes from food supply data, which measures sweeteners available for sale, including what is wasted, rather than what people eat. Survey data from the US Centers for Disease Control and Prevention give a more grounded picture: both adults and children aged 2 to 19 average about 17 teaspoons of added sugar a day. That is still far above recommended limits.

The World Health Organization advises keeping "free sugars" (sugars added to food plus those in honey, syrups and fruit juice) below 10% of daily energy, and suggests that going below 5%, roughly 25 grams or six teaspoons a day, brings extra benefits such as fewer cavities. Sugar in whole fruit, vegetables and plain milk is not counted.

The biggest single source in most diets is sugary drinks: soda, sweetened coffee and tea, energy drinks and juice. Desserts and sweet snacks follow.

Why cutting added sugar is worth it

High added-sugar diets are linked with weight gain, type 2 diabetes, tooth decay and heart disease. Some of the strongest evidence concerns drinks. A 2001 study of schoolchildren published in The Lancet found that each extra daily serving of sugar-sweetened drinks was associated with about 60% higher odds of becoming obese. In the long-running Nurses' Health Study, women who drank one or more sugary soft drinks a day had a markedly higher risk of developing type 2 diabetes than women who rarely drank them.

Older viral versions of this topic also listed cancer, dementia, depression, acne and infertility as direct results of sugar. The research there is mostly observational and mixed; excess sugar may contribute through weight gain and blood-sugar problems, but it is not proven to cause each of these conditions on its own.

On cravings, a 2013 study from Boston Children's Hospital, part of Harvard Medical School, gave overweight men two milkshakes that tasted the same and had equal calories but differed in how fast they raised blood sugar. The fast-acting shake caused a sharper rise and fall in blood sugar, more hunger later, and stronger activity in a brain reward area linked to craving. It is a small study, but it supports the idea that refined carbs can feed a cycle of hunger.

The ten steps of Hyman's plan

Hyman frames his plan as ten big ideas. In our own summary:

1. Decide whether you need it. His book includes a self-quiz about cravings, weight around the middle and energy dips.
2. Stop completely for ten days. No added sugar, no flour products and no artificial sweeteners. Ideally, eat mostly foods without an ingredients label.
3. Drop sweet drinks. Soda, juice, sports drinks and sweetened coffee and tea are out.
4. Eat protein at every meal. Eggs, fish, chicken, meat, nuts and seeds, with a palm-sized portion as a rough guide.
5. Fill up on non-starchy vegetables. Greens, broccoli, cauliflower, peppers, mushrooms, courgettes, tomatoes and similar vegetables are unlimited; potatoes and other starchy vegetables are paused.
6. Include healthy fats. Olive oil, avocado, nuts, seeds and oily fish at each meal help keep you full.
7. Carry emergency snacks. Hyman's own kit includes nut butter packets, almonds, walnuts, pumpkin seeds, jerky, canned salmon or sardines and unsweetened berries.
8. Manage stress. He suggests slow breathing before meals: five breaths in to a count of five, out to a count of five.
9. Cut gluten and dairy for the ten days. He believes these foods drive inflammation for many people.
10. Sleep properly. Poor sleep raises hunger and cravings.

What the evidence supports, and where the plan overreaches

Well supported

Cutting sugary drinks is probably the single most useful change for most people. Eating more protein, fibre-rich vegetables and unprocessed food generally improves fullness and blood sugar control. The sleep advice is also sound: in a classic 2004 study, young men restricted to four hours of sleep for two nights showed lower levels of leptin, a hormone that signals fullness, higher levels of ghrelin, a hunger hormone, and a stronger appetite for carbohydrate-heavy foods.

Overstated or unproven

• "Detox". No diet removes toxins in ten days. The real benefit is a change of habits.
• Dramatic weight loss. Promotional material for the plan said hundreds of testers lost thousands of pounds between them in ten days. Those results were self-reported, and much early loss on low-carb plans is water from depleted glycogen stores, not fat.
• Breathing and fat burning. Slow breathing can genuinely calm the stress response, but there is no good evidence that a few breaths switch the body from storing fat to burning it.
• Gluten and dairy. Coeliac disease affects around 1% of people, and many adults worldwide digest lactose poorly, but it is not true that most people have hidden sensitivities to both. Cutting them is optional, not essential.
• Artificial sweeteners. Hyman's claim that they slow metabolism is debated. Still, in 2023 the WHO advised against using non-sugar sweeteners for weight control, because long-term studies found no lasting benefit for body fat.

How to try ten lower-sugar days sensibly

• Plan the first three days. Cravings, irritability and mild headaches are common early on, especially if you also cut caffeine-heavy sweet drinks. Have meals and snacks ready.
• Read labels. Sugar hides in sauces, bread, yoghurt, cereals and ready meals under names like dextrose, glucose syrup and fruit juice concentrate.
• Keep whole fruit if you want it. The WHO limit does not apply to whole fruit, and berries are an easy swap for desserts.
• Drink water, sparkling water or unsweetened tea and coffee.
• Think about day eleven. The goal is a lower baseline you can keep, not a ten-day sprint followed by a rebound.

If you have diabetes, take blood sugar medication, are pregnant, have a history of eating disorders or have any medical condition, talk to a doctor before making big changes to your diet.

Common myths about sugar

"Natural sugars like honey and agave are fine." Your body treats honey, syrups and juice much like table sugar, and the WHO counts them as free sugars.

"Sugar is as addictive as hard drugs." Sugar does activate reward pathways, and some people find it hard to cut back, but research on true addiction in humans is far from settled.

"Fat makes you fat." Total calories and food quality matter more than fat alone; healthy fats can help you feel satisfied on fewer calories.

Sources: CDC: Get the Facts: Added Sugars; WHO sugars guideline (2015); WHO guideline on non-sugar sweeteners (2023); Wikipedia: Mark Hyman; Mark Hyman: Top 10 Big Ideas to Detox From Sugar; Ludwig et al., The Lancet (2001); Schulze et al., JAMA (2004); Lennerz et al., American Journal of Clinical Nutrition (2013); Spiegel et al., Annals of Internal Medicine (2004).