My 23-year-old sister is seriously overweight. It's not a matter of lack of knowledge about nutrition - she knows what healthy food looks like and would naturally opt for a salad rather than chips. However, her portions are very big and she eats too often. I think she associates food with love - she seems to feel that eating to excess generates good feelings, even if the results have the opposite effect on her self-esteem. As a family, we are passionate about food. We all enjoy cooking and regularly have healthy family meals together.

My sister doesn't complain about her weight, she dresses well and looks good. However, she sometimes mentions that she is larger than she would like to be. The rest of my family are naturally fairly thin. I broached the subject subtly and she got very upset. Despite this, as far as I'm aware, she has never been on a diet. Our family is close and my sister has a supportive partner, who also likes his food.

How do I get through to her, without damaging our relationship, that she will be happier if she eats less and exercises more?

Mind your own business

Your concern for your sister clearly comes from love, but you are not her doctor or her therapist, and you can't "fix" her in the way you'd like to. People who are overweight often find themselves the recipient of "helpful" advice. Imagine how you would feel if someone preached to you in this way about something you were very sensitive about - wouldn't you feel upset or angry? If you really can't leave well alone, why not suggest a fun form of exercise that you can both do together?
KM, Oxford

Your comments do not help

Your sister doesn't need reminding that she's overweight. Every time she looks in a mirror or puts her clothes on, this will be all too apparent. If you persist, you risk making her develop hang-ups about food. I also come from a family who are inclined to be thin - and my weight embarrassed me. I worked hard not to pass this mentality to my own children.
Name and address withheld

Act now to save her health

Let your sister know that the reason you're alluding to her weight is because you love her and don't want her to develop any of the diseases associated with obesity, such as diabetes or heart disease. I've lost track of the amount of middle-aged people who have told me that they regret not exercising more and taking control of their diet when they were younger. Emphasise health, not aesthetics.
JM, London

Try to boost her self-esteem

I am overweight - my BMI is 36 and has been as high as 40 - so I do understand your concerns about your sister. However, by focusing on her weight in this way, you risk making her feel like a failure. My family always made me feel this way - it didn't seem to matter to them how well I performed academically or professionally. They even offered me money to lose weight - which was even more insensitive than what you're doing.

I am fully aware that eating less and exercising more would make me happier and healthier but sadly that knowledge does not automatically lead to easy weight loss. There will still be setbacks, yo-yo dieting, despair and desperation. Accept your sister for who she is - once she feels she is free from your scrutiny she is more likely to feel empowered to do something about her weight.
Name and address withheld

There could be a medical reason

I was also the overweight sister in a skinny family; I struggled with my weight throughout my 20s, and suddenly gained more than 50lb without knowing why. I later found out that I suffer from insulin resistance and, with treatment, have dropped 40lb. Gently suggest to your sister that she gets checked out by her doctor, who will also be able to give her tips on how to eat healthily and get fit.
Name and address withheld

What the expert thinks: Linda Blair

You've decided that your sister isn't particularly happy, and that she is suffering from low self-esteem. Furthermore, you have concluded that the best way for her to overcome these problems is to eat less and exercise more. Let's take a look at your evaluation of your sister, and also at the remedy you propose for her.

You say that she's "seriously overweight". At the same time, you recognise that she "dresses well and looks good". As anyone who's seriously overweight knows only too well, the fashion industry badly neglects people over a certain size. Therefore, either your sister has terrific fashion sense and knows exactly where to shop, or she may not be as overweight as you think she is.

You also tell us that sometimes she mentions that she's larger than she'd like to be. This isn't, however, proof that she's obese. She may simply be observing - as all of us do from time to time - that she's not completely satisfied with her appearance.

On the other hand, she may be making such comments for an entirely different reason. It may be that instead of expressing a desire to be thinner, she's implying that she doesn't feel she's like the rest of the family - that she might feel her distinctiveness makes her feel excluded. What she may be hoping when she confides in you is that you'll assuage any fears she has about this. When you respond by suggesting that she needs to eat less and exercise more - however tactfully - you reinforce her perception that she's different. That will only make her feel inadequate and even more of an outsider. After all, your unsolicited advice is merely criticism by another name.

You also seem to feel it's not right that your sister associates food with love. Why not? It sounds like your entire family associates food with love - that you strengthen the bonds between you when preparing and enjoying meals together. This sounds like a very beneficial association, particularly because the foods you choose are health-giving.

The real problem is that you and your sister are caught up in a vicious cycle. She alludes to her weight, hoping you'll reassure her that regardless of this, she's a beloved member of the family. You misinterpret her requests for reassurance as expressions of dissatisfaction with her body size, and you respond by delicately suggesting she loses weight. That only makes her feel more ostracised, so she becomes even more likely to seek reassurance.

Take a fresh look at your sister. She dresses stylishly and looks attractive. She has a supportive, loving partner who fits in with your family because he loves food. She knows what foods are nutritious, and those are the foods she loves. She has a great deal going for her!

If you want to help her feel better about herself, then instead of implying that she needs to change, why not remind her of her assets whenever you can do so, with sincerity? Emphasise in particular those characteristics that she shares with the rest of you. If she ever decides to lose weight or become fitter of her own volition, no doubt she'll be able to figure out how to go about that herself.
• Linda Blair is a clinical psychologist and an associate fellow of the British Psychological Society

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