Weight gain in your 40s and how to manage this

One of the biggest paradoxes in the world is that for every 2 people in the world who are starving, 5 people are overweight or obese. According to the WHO (World Health Organisation), over 1.9 billion adults were overweight in 2014 – this is over 25% of the world’s population. Being overweight or obese increases the risk of many health issues, including cardiovascular disease, diabetes, and certain cancers.

Nearly two-thirds of adults in the UK are classed as being overweight or obese - obesity is responsible for more than 30000 deaths each year. It is estimated that the NHS in England spent £6.1 billion on overweight and obesity related illnesses from 2014 to 2015. The annual spend on the treatment of obesity and diabetes is greater than the amount spent on the police, fire service, and judicial system combined. Given that 45 – 64 year olds are the most productive age group when it comes to economics, and the age group most likely to be overweight or obese, surely it stands to reason that we need to help prevent weight gain before this time to optimize their health?

So why are we getting fatter and putting on weight? Whilst the body has complex systems to monitor how much we eat, it can’t compete with our modern lifestyles and consistent over-eating. The NHS recommended daily calorie intake is 2000kcal for women and 2500kcal for men to help the body work as efficiently as possible. If we consume more calories than we burn, we store these calories as fat. However, it’s not as simple as calories in vs calories out, as there are many reasons that we might gain weight, particularly once we are over 40 years old and female assigned at birth.

Our body has complex hormone systems to help us know how much we should eat and how much energy is stored as fat. The hypothalamus regulates food intake and monitors hormone signals from our body to regulate our appetite. Leptin is a long-term regulator of energy balance, secreted by fat cells and tells the brain how much fat the body has stored and whether we need to make If fat stores decrease, leptin levels drop and the hypothalamus stimulates us to eat. When leptin levels are high, appetite is suppressed and our brain encourages us to reduce food intake and move more to burn up fat stores.

Regular exercise, particularly moderate to high intensity interval training, can help to regulate leptin levels as can getting sufficient sleep. Conversely, ghrelin is a fast-acting hormone produced and released mainly in the stomach, which stimulates appetite, increases food intake, and promotes fat storage. Normally, your stomach releases ghrelin every 30 minutes, but this can speed up when you are really hungry. Ghrelin levels fall when food enters your large intestine, hence why it takes time to

feel full after eating.

Researchers believe that ghrelin may control stress eating as it works on the hypothalamus, which is the area in the brain responsible for emotions and pleasure seeking and this makes you crave high-calorie foods and promotes abdominal fat. University of Chicago research demonstrated that sleep deprivation increases ghrelin levels (1) , decreases helping levels and increases the risk of obesity. As the most productive age group, people over 40 are often sleep deprived and thereby their risk of over-eating and laying down fat increases. If leptin levels are decreased, the need to move decreases too, so less calories are burned. This age group is often the most sedentary with spending a lot of time sitting down at desks or on sofas or in cars. Your choice of foods is also likely to be programmed by leptin and ghrelin levels; eating simple sugars will spike ghrelin levels whilst eating more protein-rich foods (2), which keeps you fuller for longer, should decrease ghrelin levels.

Stress, anxiety and depression are a huge component of how and why eat with many people using food as a coping mechanism. This is linked to the hormone systems with cortisol, the stress hormone, being produced by the adrenal glands when the body feels stress. Chronic stress leads to permanently elevated cortisol levels which can lead to overeating high-carb and high-fat foods and weight gain (3), particularly in women. Stress relief and relaxation is particularly important for reduce cortisol levels – meditation, yoga, listening to music etc can all help.

As we age, we lose 1% of our muscle mass every year from the age of 30, mostly as we become less active. Muscles are hugely efficient at burning calories, so if you lose muscle mass, you will be burning fewer calories. If you continue to eat and drink as you have always done, and are less physically active, this increases the risk of weight gain. Adding resistance work and muscle-strengthening exercise to increase your muscle mass can counteract this reduction in metabolism (4) .

For women, oestrogen levels are also linked to hunger – lower levels in the second half of the cycle or in menopause, reduces serotonin levels and increases cortisol levels, making us feel grumpier and hungrier than usual, particularly leading to a craving of high sugar and high fat foods. Helping to balance out hormones and cravings by eating a good mix of high protein and complex carbohydrate foods, including whole grains, lentils, beans, and lots of vegetables.

Having an underactive thyroid is also another reason for weight gain; other symptoms include tiredness and depression. More older women are likely to have issues with an underactive thyroid (we don’t know why!), but this often occurs as the immune system attacks the thyroid gland so it can’t make enough thyroxine. Some medications such as lithium (used to treat mental health disorders), interferons (used to treat some cancers and hepatitis C) and amiodarone (used to treat irregular heartbeats), also increase the risk of hypothyroidism. Getting treatment from your GP to take a daily hormone replacement of levothyroxine can help.

Practical points to avoid weight gain and laying down fat from 40s onwards

1. Exercise moderately to high intensity a couple of times a week

2. Add in resistance and weight training to increase muscle mass

3. Stress relief – find a way that works for you

4. Depression – seek help for this

5. Eating a high-protein diet may help regulate ghrelin levels

6. Plan your meals to avoid feeding your cravings

Metabolic flexibility refers to the body's capability to seamlessly transition between utilizing glucose from carbohydrates and fatty acids from fats as main sources of energy. This is an essential component of metabolic health, allowing the body to adjust to different energy demands and dietary changes.

Metabolic flexibility is important for fuel adaptation and switching which can It helps maintain energy balance, preventing blood sugar fluctuations and ensuring steady energy. Poor metabolic flexibility can lead to insulin resistance, obesity, and higher type 2 diabetes risk.

Diet, exercise, and lifestyle affect metabolic flexibility. Improving metabolic flexibility involves varying your training with endurance, high-intensity, and resistance exercises; practicing carb cycling by alternating high and low carb days; incorporating intermittent fasting; and focusing on a diet of whole, unprocessed foods while limiting excessive carbs.

Genomic testing can support us to understand how your metabolism works, and what type of diet suits you best. We can then work together to understand what impacts your metabolism and hunger, and what diet and lifestyle changes will support this. If you would like to improve your health and reduce weight gain, please book in for free discovery call.

1 Elevated ghrelin predicts food intake during experimental sleep restriction.

Broussard JL, Kilkus JM, Delebecque F, Abraham V, Day A, Whitmore HR, Tasali E.

Obesity (Silver Spring). 2016 Jan;24(1):132-8

2 Nutrition targeting by food timing: time-related dietary approaches to combat obesity and metabolic syndrome.

Sofer S, Stark AH, Madar Z.

Adv Nutr. 2015 Mar 13;6(2):214-23

3 Stress, cortisol, and other appetite-related hormones: Prospective prediction of 6-month changes in food cravings and weight.

Chao AM, Jastreboff AM, White MA, Grilo CM, Sinha R.

Obesity (Silver Spring). 2017 Apr;25(4):713-720

4 Effects of Exercise and Aging on Skeletal Muscle.

Distefano G, Goodpaster BH.

Cold Spring Harb Perspect Med. 2018 Mar 1;8(3)