Advice after your nerve block for surgery
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Introduction
“Reactive hypoglycaemia” is a condition where blood sugar (glucose) may drop too low after eating, resulting in symptoms such as faintness, sweating, hunger, confusion and lack of energy.
What Changes Will I Need to Make?
Dietary advice for Reactive Hypoglycaemia focuses on aiming to maintain stable blood sugar levels. The following ideas may help:
- Have regular meals and snacks - eating regularly may be a big change for people who perhaps do not usually eat breakfast or skip meals. It is best to eat at about the same time each day. This helps keep the amount of glucose in your blood stream stable. You should not skip meals or snacks as this can cause your blood glucose to drop too low. Aim to have something to eat as soon as possible after you get up and have a starchy bedtime snack.
- Include some starchy food at every meal as part of a balanced meal - starchy foods such as bread, potatoes, rice, pasta, chapattis and breakfast cereals give you energy and help keep your blood sugars stable.
- Avoid having sugary foods and drinks on a regular basis e.g. Sweets, cakes, desserts, sugary breakfast cereals, ordinary squashes and fizzy drinks - most people will need to cut down on the amount of sugary food and drinks they have or replace them with low-sugar alternatives. Sugary foods and drinks are quickly digested and absorbed into the blood stream causing blood glucose to rise quickly, followed by dropping too low later.
- Try to choose “slow release” starchy foods as often as possible.
- It is best to follow a healthy, balanced diet for general health and to prevent weight gain.
How Can I Eat Less Sugar?
One of the ways you can help control your blood glucose is not to have a lot of sugary foods and drinks. Foods which contain a lot of sugar will usually cause a sudden rise in blood sugar levels, particularly if eaten on an empty stomach; this in turn has the potential to lead to a sudden drop in blood sugar levels later.
If you do want to eat a food with a high sugar content, have a small portion at the end of a meal rather than between meals. This will slow down the rate at which the sugar is absorbed into the blood stream and consequently how quickly it will cause blood sugar levels to rise.
Cutting out foods with a high sugar content does not mean that you should have diabetic sweets, biscuits, cakes and chocolates instead. These products are generally very expensive and can cause diarrhoea due to the artificial sweeteners they contain. Using diabetic products is not necessary
for good blood sugar control.
| Foods containing a lot of sugar | Choose low sugar / Sugar-free alternatives |
| Sugar, glucose, dextrose and sucrose | Artificial sweeteners e.g. Splenda, Hermesetas, Canderel, Sweetex, Stevia |
| Jam, marmalade, honey, lemon curd, treacle and golden syrup | Reduced sugar jams ands marmalades, pure fruit spreads |
| Sweet drinks e.g. cola, fizzy drinks, fruit squash (including no added sugar, high juice content), Lucozade, milk shakes, fruit juice, some smoothies | Diet fizzy drinks, no added sugar squash, soda water, mineral water, milk |
| Sweets, chocolate, mints, chewing gum |
Sugar free chewing gum e.g. Orbit, Extra, sugar-free mints/sweets e.g. Sula, Extra Mints |
| Sugar or honey coated breakfast cereals, e.g. Sugar Smacks, Frosties |
Low sugar breakfast cereals e.g. Weetabix, Shredded Wheat, porridge, unsweetened muesli, Special K |
| Chocolate coated and cream filled biscuits |
Plain biscuits in moderation e.g. rich tea, digestives, crispbreads, oatcakes |
| Yoghurts, fromage frais | ‘Diet’ yoghurts and fromage frais e.g. Shape, Ski Smooth, Weight Watchers, Muller Light |
| Sweet puddings, crumbles, sponge puddings, trifle, cheesecake, mousse, instant and tinned puddings, fruit in syrup |
Fruit in natural juice, sugar-free jelly, no added sugar/sugar-free puddings, e.g. instant whip, custard, low sugar rice pudding. Homemade sugar-free puddings e.g. rice, semolina, custard (with sweetener to taste) |
| Cakes, pies, tarts. | Low sugar baked foods (use half amount of sugar) e.g. scones, tea breads, hot cross buns |
| Sweetened condensed milk, drinking chocolate |
Evaporated milk, cocoa, ‘Lite’ varieties of milky drinks e.g. Highlights, Options, Ovaltine Light |
“Slow Release” Carbohydrate Foods
As mentioned before, starchy foods (carbohydrates) such as bread, potatoes, rice, pasta, chapattis and breakfast cereals help to keep blood sugars stable. However, some starchy foods cause a much slower rise in blood sugar levels than others and are, therefore, better at keeping blood sugar levels stable.
The Glycaemic Index (GI) is a system of ranking starchy foods according to their effects on blood sugar levels. Eating starchy foods with a low GI (“slow release”) cause a slow, steady rise in blood sugar levels, while those with a high GI (“fast release”) cause blood sugar levels to rise more quickly.
Introducing more low-GI or “slow release” starchy foods into meals can help to maintain blood sugar levels between meals and can, therefore, help prevent low blood sugar levels.
The GI of a food is related to how quickly or slowly a food is digested. There are a number of factors that can affect this.
These include:
- The structure of the starch in the food
- The type and amount of fibre in the food
- The type and amount of sugar in the food
- The presence of fat, protein or acid in the food
- The degree of processing the food has undergone
| Low GI Foods (Slow-Release Carbohydrates) |
Medium GI Foods (Medium Release Carbohydrates) |
High GI Foods (Fast Release Carbohydrates) |
| Apples, oranges, pears, peaches, plums, grapefruit, grapes, apricots (fresh or dried), banana (yellow with green sections), mango, strawberries, cherries, blueberries |
Banana (yellow with black spots), melon, dried fruit, pineapple, dates, kiwi, raisins |
Watermelon |
| All beans, lentils, chickpeas, split peas. Nuts and seeds |
||
| White or wholemeal pasta, egg pasta |
Gnocchi, udon noodles, rice vermicelli noodles |
Gluten free pasta, corn pasta, rice pasta, canned spaghetti |
| Brown rice, bulgar wheat, buckwheat, quinoa, pearl barley, microwave rice |
Basmati rice, wild rice, couscous, Arborio rice, polenta, Long grain rice |
Short grain rice, fast cook long grain rice, sushi rice, jasmine rice, instant rice, tapioca |
| Rolled oats, no added sugar muesli, All Bran, porridge, Bran Flakes |
Mini wheats, Shredded Wheat, Weetabix, Oatibix, instant porridge, Special K, Fruit and Fibre. Sultana Bran |
Cornflakes, Crunchy Nut Cornflakes, Rice Krispies, puffed wheat, Coco Pops, Cheerios |
| Multi-grain or mixed-grain bread, soya and linseed bread, granary bread, oatbran bread, chapattis, rye bread, tortilla wraps, fruit loaf, sourdough, seeded bread, pumpernickel bread |
Crumpets, rye crisp bread, pitta bread, croissant, taco shells, malt bread |
White, wholemeal and brown bread, baguettes, bagels, melba toast, Naan bread, English muffins |
| Oat cakes, Rich Tea biscuits, fruit loaf, tea cakes, Ryvita with seeds |
Ryvita, plain digestive biscuits, shortbread, muesli bars, popcorn (plain/salted), flapjack, crisps |
Waffles, water biscuits, rice cakes, cream crackers, corn thins, pretzels |
| Milk (all dairy), low fat yoghurt, ice cream, custard, soya products |
Sorbet, oat milk | Rice milk |
| Sweet potato | New or boiled potatoes, chips/fries |
Jacket/mashed/instant potato |
Suggested Meal Plan
Aim to have meals/snacks every 2-3 hours
Breakfast
- Fruit/ 150ml fruit juice
- High fibre cereal or porridge or no added sugar muesli or granary toast with reduced sugar jam/marmalade
Mid-morning
- Slice of granary bread or toast or wholemeal crispbreads
Lunch
- Lean meat or chicken or fish or egg or beans or cheese
- Vegetables or salad
- Granary bread or potato or rice or pasta.
- Fruit, or low-sugar yoghurt or fromage frais, or low-sugar dessert
Mid-afternoon
- Fruit or plain biscuit e.g. Rich Tea biscuits or oatcakes
Evening Meal
• As lunch
Bedtime Snack
• Oatcakes or wholemeal crispbreads with low-fat soft cheese, or wholegrain cereal and milk
Contact us
If you have any queries relating to this information, please contact the Dietetics service.
About this information
Service:
Dietetics
Reference:
DT/019
Approval date:
1 March 2026
Review date:
1 March 2029
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Important note
This page provides general information only. It is developed by clinical staff and is reviewed regularly every 3 years for accuracy. For personal advice about your health, or if you have any concerns, please speak to your doctor.