Nutrition and chronic fatigue syndrome: what to eat and how to plan

What is chronic fatigue syndrome?

Chronic fatigue syndrome, or myalgic encephalomyelitis (CFS/ME), is a chronic illness that affects several body systems. Its central feature is intolerance to exertion. The US Institute of Medicine consensus report set out its diagnostic criteria in 2015 [2]. The first is a substantial reduction in the level of activity a person had before, lasting more than six months. It is accompanied by profound fatigue with a clear onset, which is not explained by recent exertion and is not clearly improved by rest [2].

What distinguishes it from other kinds of tiredness is post-exertional malaise [2]. This is a disproportionate worsening of symptoms after physical, mental or emotional activity that used to be trivial, such as grocery shopping or having a conversation. It often begins hours or days later, and recovery can take hours, days, weeks or longer [1]. That is why you might feel fine on the day of a family meal and notice the effects two days later.

The criteria also include unrefreshing sleep and one of two symptoms [2]. One is cognitive difficulty, often called brain fog. The other is orthostatic intolerance, which can cause dizziness or palpitations on standing. A doctor makes the diagnosis after ruling out other causes of fatigue. No nutritional test, commercial IgG food intolerance test or hair analysis can diagnose this illness.

Is there a diet that can resolve chronic fatigue syndrome?

No. There is currently no treatment, pharmacological or otherwise, that resolves the illness. UK clinical guidelines say this should be explained clearly and that medicines or supplements should not be offered with that promise [1]. Any proposal promising remission through food has no scientific basis.

Those same guidelines do give nutrition a role in day-to-day care. They stress drinking enough and eating a balanced diet [1]. They also recommend helping with nausea, appetite changes, difficulty swallowing and the effort involved in shopping, cooking and eating [1]. Food can support you. It can help prevent deficiencies that add to fatigue, make digestion more manageable, and adapt meal times and textures so eating takes less energy.

If you are losing weight and at risk of malnutrition, gaining weight or following a restrictive diet, it is worth seeing a registered dietitian with experience in CFS/ME [1]. Restrictions without medical advice can be physically and emotionally draining. They can also make it easier to eat less protein and energy than you need. A helpful eating plan is flexible, individual and designed to make your day easier.

Which foods help maintain energy?

No specific food or eating pattern has been shown to improve the illness. A review of seventeen studies concluded that there is not enough evidence to recommend supplements or elimination diets [3]. So we start with what works for anyone: a varied Mediterranean-style diet based on fresh and minimally processed foods, the same foundation as our guide to anti-inflammatory nutrition.

To keep your energy steadier, choose slow-release carbohydrates, such as oats, rice, potatoes, sweet potatoes, wholemeal bread or well-cooked pulses. Combined with protein and a little fat in a meal, they are digested more gradually. This can make it easier to avoid an energy dip before your next meal. If a large serving feels too heavy, divide the same amount into two smaller meals.

Protein helps preserve muscle mass when activity is very limited, so try to include a portion with each main meal. Extra virgin olive oil, avocado and nuts complete the meal. For ideas with oily fish and seeds, see the guide to foods rich in omega-3. Seasonal vegetables and fruit provide fibre, vitamin C and potassium; cook them or choose ripe options if digestion is sensitive.

If you spend a lot of time at home or in bed, you may be at risk of vitamin D deficiency, and the guidelines refer to their specific protocol for assessing whether a supplement is needed [1]. Your doctor decides, based on a blood test.

Why are digestive problems common in people with chronic fatigue syndrome?

Many people with CFS/ME experience bloating, slow digestion, abdominal pain, nausea or changes in bowel habits. These symptoms are common in the illness, although they are not part of the diagnostic criteria [2]. UK guidelines treat them as problems to address with the person [1]. Several mechanisms have been proposed. One is the gut–brain axis, the relationship between the nervous and digestive systems. Another is dysfunction of the autonomic nervous system, the part that regulates automatic functions such as digestion and blood pressure.

In consultations, people often say that a large meal leaves them more tired and feeling heavy for hours. It may feel better to divide what you eat into four or five smaller meals, chew slowly and use simple cooking methods such as steaming, baking, boiling or grilling. If you feel nauseous, keep drinking and eat regularly, little and often, because not eating or drinking can make nausea worse [1].

If your doctor has also diagnosed you with irritable bowel syndrome, a low-FODMAP diet may relieve pain and gas. The elimination phase lasts 2 to 6 weeks, with an end date set from the first day. Then reintroduce foods with professional supervision to avoid making your diet unnecessarily limited.

Do supplements help with chronic fatigue?

Many supplements are sold, but the supporting evidence is limited and inconsistent [4]. Coenzyme Q10 and NADH, the reduced form of nicotinamide adenine dinucleotide, are involved in energy production in mitochondria, the cell structures that produce it. Some trials have found modest improvements in fatigue with NADH, alone or together with coenzyme Q10 [3] [4]. These are small, short studies using different methods, and they are not enough to recommend these supplements [3].

Vitamins and minerals are similar. The European Union authorises claims that folate, iron, magnesium, vitamin B12 and vitamin C, among others, contribute to the reduction of tiredness and fatigue [5]. This is a claim about their normal function in the body. It applies when a confirmed deficiency needs correcting [4].

There is also no evidence for routinely taking vitamin and mineral supplements for the illness or its symptoms, and doses above recommended amounts can have effects you should know about [1]. If a blood test shows iron deficiency, start with food; we explain this in our guide to nutrition for anaemia. Your doctor or registered dietitian should advise on any supplement, according to your situation and after appropriate blood tests.

On a flare-up day

During an episode of post-exertional malaise, often called a crash, basic tasks can feel impossible. Standing to peel vegetables, watching a pan or washing up can use up the day’s energy and prolong the flare-up. That day, the priority is to eat enough with as little physical and mental effort as possible.

It helps to keep a flare-day pantry stocked with ready-to-eat foods. Tinned pulses only need rinsing under the tap before you combine them with preserved vegetables such as roasted peppers, asparagus or artichokes. Tinned fish in water or olive oil, such as mackerel, small sardines, frigate tuna or tuna, and boiled eggs provide protein with almost no preparation.

Other useful options include packaged soups containing only vegetables, water and oil; microwave rice or quinoa cups; and mild gazpacho. If chewing is difficult, choose soft textures. Try a purée with a poached egg, plain yoghurt with peanut butter, or a smoothie made with milk or soy drink, fine oats and a ripe banana. If swallowing is difficult, discuss it with your doctor.

For advance meal planning, the weekly menu for fibromyalgia may be a useful starting point, as it follows many of the same principles.

How is chronic fatigue syndrome different from fibromyalgia?

They are two distinct illnesses that share many symptoms, including fatigue, pain, unrefreshing sleep and difficulty concentrating. They often occur together in the same person and can be confused at first.

The difference lies in the main symptom. In fibromyalgia, the central feature is widespread, persistent musculoskeletal pain, with stiffness and increased sensitivity to touch and pressure. Stimuli that would not normally hurt, or would hurt only slightly, are experienced as painful. Fatigue and poor sleep are common, but they do not define the illness.

In chronic fatigue syndrome, the defining features are profound exhaustion and post-exertional malaise after minimal activity [2]. Pain can occur, but it is usually less prominent than exertion intolerance and cognitive difficulties. The basic approach to eating is similar. If pain is the main concern, see the guide to nutrition for fibromyalgia.

If you feel dizzy when standing up

Orthostatic intolerance is part of the CFS/ME criteria [2]. It can present as postural orthostatic tachycardia syndrome (POTS), an excessive increase in heart rate on standing [1]. Symptoms can include dizziness, feeling faint, blurred vision, palpitations or weakness when you stand up or remain standing for a while.

From a nutrition perspective, the main thing is to avoid drinking too little. Sip water, herbal teas or broths throughout the day unless kidney or heart disease means your fluids need to be limited. As a general reference, EFSA estimates total water intake of 2 L per day for women and 2.5 L for men, including water from food. Needs vary with age, heat, exercise, pregnancy and breastfeeding. If you have orthostatic intolerance, your doctor will adjust the amount for you.

For some people with confirmed orthostatic intolerance and low blood pressure, a doctor may recommend somewhat more salt, with blood pressure monitoring. This is not something to do on your own. For other adults, the general reference is less than 5 g of salt per day (about 2 g of sodium). Medication for orthostatic intolerance should be prescribed or supervised by an experienced healthcare professional, who can refer you to a specialist if symptoms are severe or worsening [1]. If advised, broth or seasoning food a little more is enough; special products are not needed.

What mistakes come up in consultations?

• Cutting out whole food groups based on suspicions, without a diagnosis to justify it. This often leads to deficiencies, muscle loss and more fatigue.
• Using coffee, strong tea or energy drinks to get through the day. They mask fatigue for a few hours; you do more than your body can tolerate, and post-exertional malaise follows. If coffee agrees with you, there is no need to stop; just do not use it to push yourself.
• Spending the day’s energy on complicated shopping and time-consuming recipes. A simple meal that is easy to put together can still be nutritious.
• Waiting for a good day to do a large shop and cook for the whole week. That effort can take its toll afterwards, and is often more manageable when divided into short periods.
• Starting several supplements at once without blood tests or professional advice. There is a risk of interactions, and the expense may not be worthwhile.
• Ignoring unintentional weight loss or eating less and less because it takes effort. This is a reason to ask your doctor and a registered dietitian for help [1].