Most people are aware that a healthy diet is vital in order to reduce the risk of heart disease, diabetes, obesity and other common physical problems. Recent evidence also suggests that good nutrition may be just as important for our mental health and that a number of conditions, including depression, may be influenced by dietary factors. Research in this area is still taking place and although the evidence is mixed there does appear to be a strong correlation between what we put in our mouths and impact on our minds.
Below are some of the ‘non-negotiables’ that you should consider making a part of your life where you can, if you goal is to maintain good mental and physical health.
• Eat regularly throughout the day
• Choose less refined high sugar foods and drinks and more wholegrain cereals, pulses, fruit and vegetables
• Include protein at each meal
• Eat a wide variety of foods
• Include oily fish (omega 3 fatty acids) in your diet
• Maintain a healthy weight
• Maintain adequate fluid intake
• If you drink alcohol keep within recommended limits
• Exercise regularly
This list is for anyone who wishes to protect their mental health through healthy eating. It is particularly relevant for people recovering from mild or moderate depression and suggests how changes to their diet can help improve their mood. People with severe depression are encouraged to seek medical/professional help as a priority. While a healthy diet can help with their recovery, it should sit alongside other treatments recommended by your doctor or health professional.
1. Eat regular meals throughout the day to maintain constant blood sugar
Make sure you eat at least three meals each day. Missing meals, especially breakfast, leads to low blood sugar and this causes low mood, irritability and fatigue. If you feel hungry between meals you may need to include a healthy snack e.g. fruit/nuts/cereals are good choices.
2. Choose less refined high sugar foods and more wholegrain cereals, nuts, beans, lentils, fruit and vegetables
Sugary foods are absorbed quickly into the bloodstream (they may also be referred to as high glycaemic index foods). This may cause an initial ‘high’ or surge of energy that soon wears off as the body increases its insulin production, leaving you feeling tired and low.
Wholegrain cereals, pulses, fruit and vegetables are more filling and generally have a lower glycaemic index than processed foods. Because the sugar in these foods is absorbed more slowly it prevents mood swings. These foods are also nutritionally much better, containing thiamin (B1), a vitamin that has been associated with control of mood, and folate and zinc (supplements of these nutrients have been shown to improve the mood of depressed patients).
Better Choices Include:
• Breads - select wholemeal and granary types rather than white. Also try rye breads, pumpernickel, wholemeal pitta bread, wholemeal chapattis, oat cakes, rice cakes and corn cakes.
• Breakfast cereals – choose high fibre, low sugar types e.g. wholegrain or bran cereals or porridge.
• Rice and pasta - choose Basmati and brown rice. Use wholemeal pasta.
• Potatoes - serve boiled new potatoes in their skins (with a minimum amount of butter) or mashed or jacket potatoes. Potato wedges (lightly brushed with olive oil) are a lower fat alternative to chips and roast potatoes for those watching their weight. Try sweet potatoes or yams for a change - these are delicious baked and also have a low glycaemic index.
• Aim to eat at least 5 portions of fruit and vegetables a day e.g. 1 glass of orange juice or 1/2 grapefruit for breakfast, a banana or apple for a mid morning snack, salad at lunch time and then two types of vegetable (a portion is roughly 2 serving spoons) and a pear or baked fruit at the evening meal.
NB: Green vegetables should be cooked in a small amount of pre-boiled water, and should not be overcooked or you will lose much of the vitamin content. Avoid sugar and sugary drinks, cakes, sweets and puddings. These are loaded with calories but have little nutritional value and may trigger a mood swing.
3. Include protein at each meal to ensure a continuous supply of the amino acid tryptophan to the brain
We all need to eat enough protein to maintain our skin, organ, muscle and immune function but recent research suggests that one particular component of protein, the amino acid tryptophan, is important in its effect on the brain, where it influences mood. Supplements of tryptophan were tested in studies and in some were shown to improve the mood of depressed individuals.
However, you can ensure your brain gets a regular supply of tryptophan by including at least one good sized portion of protein at each meal i.e. meat, fish, eggs, milk, cheese, nuts, beans, lentils (dhal), or a meat substitute such as textured vegetable protein or mycoprotein. NB: peanuts are low in tryptophan so if you eat them at a meal-time include another source of protein (e.g. other nuts) at the same time.
4. Eat a wide variety of foods to keep your diet interesting and to ensure you obtain all the micronutrients you need
The more varied your diet, the more likely you are to obtain all the nutrients you need. If you have bread at one meal, try cereal or potatoes, rice or sweet potatoes at the others. Make sure you include at least two portions of different fruits and/or vegetables and a protein food at each meal. Include some red meat and fish, as they are good sources of vitamin B12, another nutrient that seems to be associated with the control of mood. If you are vegetarian or have a limited budget, include fortified soy mince and yeast extract to increase your intake of this vitamin.
5. Include fish, especially oily fish, in your diet
A few studies suggest that supplements of omega 3 oils may reduce symptoms in patients with depression on antidepressant medications. These studies are small but we know that a proper balance of omega 3 and omega 6 oils in the diet is important. It has been suggested that many of the modern inflammatory diseases may be due to an imbalance between the two.
In order to improve the balance:
• Include more omega 3 rich oily fish in the diet from sustainable fish stocks -between 2-4 portions weekly for most adults (but no more than 2 portions if you are pregnant or breastfeeding). If buying tinned fish, choose varieties in water, brine or tomato sauce rather than in sunflower oil (high in omega 6).
• If you fry food (e.g. stir-fries) use an oil high in monounsaturates e.g. olive or rapeseed oil. Coconut oil is also very good for frying.
• Choose a monounsaturated margarine or butter for spreading. Avoid margarines or low fat spreads containing omega 6 polyunsaturated or hydrogenated trans fats (trans fats are damaging to your brain and arteries).
• Avoid processed foods such as pies, sausage rolls, crisps and cakes that are high in saturated and trans fats.
6. Maintain a healthy weight
Depression affects different people in different ways. Some people lose interest in food or can’t be bothered to shop and cook, so lose weight. Others find they want to eat more when they are unhappy and gain weight. Anti-depressants can also significantly increase or decrease your appetite – if you are concerned that the medication you are taking has made your problems worse, speak to your doctor.
Both excessive weight loss or weight gain can make your mood worse and should be avoided. Weight loss and lack of good nutrition will deprive the brain of glucose and the other nutrients that control mood – you may need the advice of a nutritionist or dietitian to help you overcome this problem.
Putting on weight unintentionally or feeling out of control of your eating can increase your depression and can lead to yo-yo dieting which leaves you further out of control. If you are overweight, follow the advice in previous sections but be extra careful to limit your fat and sugar intake, use less fat in cooking, reduce your alcohol consumption and increase your exercise levels.
7. Maintain adequate fluid intake
Not drinking enough fluid has significant implications for mental health. The early effects of even mild dehydration can affect our feelings and performance, often characterised by restless or irritable behaviour.
During an average day in the UK an adult’s body loses approximately 2.5 litres of water through the lungs as water vapour, through the skin as perspiration and/or through the kidneys as urine. If sufficient fluids are not consumed to replace this loss then the symptoms of inadequate hydration can appear, including increased irritability, loss of concentration and reduced efficiency in mental tasks. There is growing evidence that even a 2% reduction in water intake can have substantial implications on one’s mental health and sense of wellbeing.
Coffee, colas, some energy drinks and tea all contain caffeine, which some people use to boost energy levels. However, evidence suggests that in large quantities caffeine can increase blood pressure, anxiety, depressive symptoms and sleep problems. Caffeine also has a diuretic effect in the body that encourages the production of urine and therefore the release of fluids. For this reason you should not rely solely on caffeine based fluids.
If you do choose to use caffeinated drinks it is advisable to limit caffeine intake to the equivalent of no more than 3-4 cups of coffee per day and to drink other fluids such as water, fruit juice and non-stimulant herbal teas at other times. Remember chocolate also contains caffeine and should be limited to an occasional treat.
8. Limit your alcohol intake
Alcohol has a depressant effect on the brain so can result in a rapid worsening of your mood. It is also a toxin that has to be deactivated by the liver. During this detoxification process the body uses thiamin, zinc and other nutrients and this can deplete your reserves, especially if your diet is poor. Thiamin and other vitamin deficiencies are common in heavy drinkers and these deficits can cause low mood, irritability and/or aggressive behaviour as well as more serious and long-term mental health problems.
Because the body uses important nutrients to manage the processing of alcohol, people who experience depression should consider abstaining from alcohol use until they have recovered. Even then, because of alcohol’s depressant effects they should consider drinking only small amounts, perhaps no more than once a week.
If you do wish to drink alcohol it is important not to exceed the recommended safe limits i.e. 14 units for women and 21 units for men per week and to also have at least one or two alcohol free days a week.
9. Exercise regularly
Exercise leads to the release of endorphins - feel good chemicals that help us to relax and to feel happy. Exercise is particularly important for those with depression as it also gives structure and purpose to the day. Outdoor exercise that exposes us to sunlight is especially valuable as it affects the pineal gland, directly boosting mood.
If you are trying to control your weight, exercise has some other advantages too. For example, the more you exercise, the less you need to cut down on your calorie intake to control your weight. It is also beneficial for heart health and it ensures that as fat is lost muscle is still retained, resulting in a more toned body. Exercise also prevents the loss in bone mass and increased risk of osteoporosis that can occur with dieting in the absence of exercise.
There is no need to join a gym - walking is the easiest and best form of exercise and it can be built up as your fitness level increases. Swimming is good for those who have joint problems and find it difficult to weight-bear and cycling is also an effective way to stay fit. Whatever kind of exercise you choose, try to start with 20 minutes at least three times a week and increase as your fitness improves.
10. Nutritional supplements
The evidence around nutritional supplements is still mixed, although the orthomolecular medicine experts have been saying from the 1950s what Plato said some 400 years before Christ – in summary, ‘you cannot fix the mind without fixing the body and you cannot fix the body without fixing the mind’. The deficiencies in the soil and the pollution that we are generally battling with each day have compromised the nutrients now found in our food and so an alternative is needed. Currently supplements appear to be our best option. So if this is something you’re going to pursue, the quality of the product is paramount.
• Choose a complete 1-a-day multivitamin / mineral preparation containing the full recommended daily intake of each vitamin and mineral. These products are relatively safe as they do not contain excessive amounts of any single nutrient (but you should avoid other supplements containing these nutrients, in particular vitamin A as it is toxic in high doses)
• If your doctor prescribes vitamins or minerals for you make him/her aware of the products you are already taking.
• If you do take a multivitamin supplement, avoid liver and other offal products, such as pate, as these are also high in vitamin A.
• It is important to remember that supplements are not an alternative to a healthy diet and you should still maintain a varied and balanced diet.
• You may need professional advice/guidance to work out the best nutritional programme for you. Do not just buy things based on a news item, an article you’ve read or something on the internet.