
6 things you should consider before starting a diet
Tempted to try the latest diet du jour? Make sure you have all the facts first. From fasting 5:2 to carb-curbing Paleo, here are the six things you should consider before starting any diet...
It's almost impossible to keep up with all the different diets that come in and out of the spotlight each month, and with the emergence of numerous Instagram and YouTube healthy eating 'gurus', it can be hard to distinguish between informed nutritional advice and fad diets. Here are six questions you should ask before embarking on any weight loss plan to help you determine if it will be effective and, most importantly, safe for you...
Does it provide enough kcalories (kcals)?
The average daily requirement for a moderately active adult is 2,500 kcals for men and 2,000 kcals for women but when dieting, you’ll need to reduce your energy intake in order to burn off more than you consume.
Nutritionist Kerry Torrens says, "A general guide is to aim for fat loss of 1lb per week. To achieve this, it's suggested that you create a deficit of 500 calories a day from your normal eating plan. The best way to start is to keep a food diary so you understand exactly how much, what and when you're eating and drinking."
Identify where you can cut excess or empty calories, and focus instead on making your meals nutrient-dense by including leafy greens such as kale, spinach and rocket, as well as wholegrains such as quinoa and barley, along with plenty of fruit and vegetables. Swapping sugar-sweetened or alcoholic drinks for low-calorie options is a good way to cut back on calories without feeling hungry.
Children, teenagers and pregnant women will have special calorie requirements, and should be supervised by a doctor when embarking on any restrictive eating plan. Similarly, those with a diagnosed medical condition should refer to their GP prior to commencing a weight loss plan.
Take our quiz to find out how many calories are in your favourite alcoholic beverages.
Is it balanced?
Diets that encourage cutting out or severely restricting entire food groups or macronutrients (e.g. carbohydrates) are likely to be unbalanced and difficult to maintain. Any diet that promotes eating mainly one type of food (such as the cabbage soup diet) may also put you at risk of nutritional deficiencies. Read our advice on eating a balanced diet to get an idea of what you need, whether you're male, female, vegetarian or vegan.
Is it sustainable?
Can you stick to the plan for a long period of time? What happens when the diet period is over, or you reach your goal? Maintaining a healthy weight and eating a balanced diet is something that you need to fit into your lifestyle permanently – if you revert back to your old eating habits, you're likely to put the weight back on. Can you make your chosen style of eating fit around your commitments? If you eat out or travel a lot for work, try to plan in advance how you could work around these. If a plan is too rigid and prescriptive you'll have a hard time following it in the long-term.
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Is it scientifically sound?
This is one of the hardest questions to answer. Looking into the background and qualifications of the person behind the diet might give you some indication of its legitimacy, but sometimes the answer isn’t that simple. As Kerry points out, "Even plans developed by trained medical practitioners are not without their critics – Atkins for example was formulated by an American Cardiologist, yet it recieved a huge amount of criticism, and still does. If you want guidance and reassurance that you're following a well-balanced diet you should seek the help of a registered dietitian."
Is the final goal realistic?
Diets which promise dramatic weight loss are unlikely to deliver the quick-fix results you’re after, and even if they do, they may not be desirable. ‘As a general guide, between 0.5lb and 2lbs a week is considered a safe amount of weight loss per week’, Kerry says. It's also important to aim for a suitable goal weight - even if you lose the weight slowly and sensibly, you don't want to risk losing too much and becoming underweight. The NHS offer an easy-to-understand tool to calculate your BMI - use this to work out what your BMI is right now, and whether your target weight is healthy for you.
Is it safe?
Just because friends or family have had success with a particular diet doesn't mean that it is the right plan for you too. It's always advisable to see your GP before starting a weight loss plan, but especially important for those with existing medical conditions, including any history of eating disorders.
Read more about popular diets....
What is the 5:2 diet?
What is the Paleo diet?
What is the Atkins diet?
What is the Dukan diet?
Read up on more popular diets
Have you tried, or been tempted to try, a weight loss plan? Let us know in the comments below...
This article was last reviewed on 8 July 2019 by Kerry Torrens.
A qualified nutritionist (MBANT), Kerry Torrens is a contributing author to a number of nutritional and cookery publications including BBC Good Food magazine. Kerry is a member of the The Royal Society of Medicine, Complementary and Natural Healthcare Council (CNHC), British Association for Applied Nutrition and Nutritional Therapy (BANT).
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